CVE-2024-6839
Improper Regex Path Matching in corydolphin/flask-cors
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
4.3
Improper Regex Path Matching in corydolphin/flask-cors
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
CVE-2024-6839- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-41
- Updated
- 2026-11-02
EUVDEUVD-2025-6973
4.3
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
EUVD-2025-6973- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7rxf-gvfg-47g4
4.3
Flask-CORS improper regex path matching vulnerability
corydolphin/flask-cors version 5.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
GHSA-7rxf-gvfg-47g4- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-41
- Updated
- 2026-11-02
NVD
5.3
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
CVE-2024-6839- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-41
- Updated
- 2026-11-02
OSV
4.3
Improper Regex Path Matching in corydolphin/flask-cors
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
CVE-2024-6839- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-41
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2024-6839
5.3
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
DEBIAN-CVE-2024-6839- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
Show 13 moreShow less
OSVGHSA-7rxf-gvfg-47g4
4.3
Flask-CORS improper regex path matching vulnerability
corydolphin/flask-cors version 5.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
GHSA-7rxf-gvfg-47g4- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-41
- Updated
- 2026-11-02
OSVOESA-2025-1938
5.3
python-Flask-Cors security update
A Flask extension for handling Cross Origin Resource Sharing (CORS), making cross-origin AJAX possible.
Security Fix(es):
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.(CVE-2024-6839)
A vulnerability in corydolphin/flask-cors version 4.0.1 allows for inconsistent CORS matching due to the handling of the '+' character in URL paths. The request.path is passed through the unquote_plus function, which converts the '+' character to a space ' '. This behavior leads to incorrect path normalization, causing potential mismatches in CORS configuration. As a result, endpoints may not be matched correctly to their CORS settings, leading to unexpected CORS policy application. This can cause unauthorized cross-origin access or block valid requests, creating security vulnerabilities and usability issues.(CVE-2024-6844)
corydolphin/flask-cors version 4.01 contains a vulnerability where the request path matching is case-insensitive due to the use of the try_match function, which is originally intended for matching hosts. This results in a mismatch because paths in URLs are case-sensitive, but the regex matching treats them as case-insensitive. This misconfiguration can lead to significant security vulnerabilities, allowing unauthorized origins to access paths meant to be restricted, resulting in data exposure and potential data leaks.(CVE-2024-6866)
- Record
OESA-2025-1938- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVOESA-2025-1939
5.3
python-Flask-Cors security update
A Flask extension for handling Cross Origin Resource Sharing (CORS), making cross-origin AJAX possible.
Security Fix(es):
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.(CVE-2024-6839)
A vulnerability in corydolphin/flask-cors version 4.0.1 allows for inconsistent CORS matching due to the handling of the '+' character in URL paths. The request.path is passed through the unquote_plus function, which converts the '+' character to a space ' '. This behavior leads to incorrect path normalization, causing potential mismatches in CORS configuration. As a result, endpoints may not be matched correctly to their CORS settings, leading to unexpected CORS policy application. This can cause unauthorized cross-origin access or block valid requests, creating security vulnerabilities and usability issues.(CVE-2024-6844)
corydolphin/flask-cors version 4.01 contains a vulnerability where the request path matching is case-insensitive due to the use of the try_match function, which is originally intended for matching hosts. This results in a mismatch because paths in URLs are case-sensitive, but the regex matching treats them as case-insensitive. This misconfiguration can lead to significant security vulnerabilities, allowing unauthorized origins to access paths meant to be restricted, resulting in data exposure and potential data leaks.(CVE-2024-6866)
- Record
OESA-2025-1939- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVOESA-2025-1981
5.3
python-Flask-Cors security update
A Flask extension for handling Cross Origin Resource Sharing (CORS), making cross-origin AJAX possible.
Security Fix(es):
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.(CVE-2024-6839)
A vulnerability in corydolphin/flask-cors version 4.0.1 allows for inconsistent CORS matching due to the handling of the '+' character in URL paths. The request.path is passed through the unquote_plus function, which converts the '+' character to a space ' '. This behavior leads to incorrect path normalization, causing potential mismatches in CORS configuration. As a result, endpoints may not be matched correctly to their CORS settings, leading to unexpected CORS policy application. This can cause unauthorized cross-origin access or block valid requests, creating security vulnerabilities and usability issues.(CVE-2024-6844)
corydolphin/flask-cors version 4.01 contains a vulnerability where the request path matching is case-insensitive due to the use of the try_match function, which is originally intended for matching hosts. This results in a mismatch because paths in URLs are case-sensitive, but the regex matching treats them as case-insensitive. This misconfiguration can lead to significant security vulnerabilities, allowing unauthorized origins to access paths meant to be restricted, resulting in data exposure and potential data leaks.(CVE-2024-6866)
- Record
OESA-2025-1981- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVPYSEC-2026-1384
4.3
Flask-CORS improper regex path matching vulnerability
corydolphin/flask-cors version 5.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
PYSEC-2026-1384- CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2024-6839
5.3
corydolphin/flask-cors version 4.0.1 contains an improper regex path matching vulnerability. The plugin prioritizes longer regex patterns over more specific ones when matching paths, which can lead to less restrictive CORS policies being applied to sensitive endpoints. This mismatch in regex pattern priority allows unauthorized cross-origin access to sensitive data or functionality, potentially exposing confidential information and increasing the risk of unauthorized actions by malicious actors.
- Record
UBUNTU-CVE-2024-6839- CVSS 3.1
- 5.3 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N - CVSS 3.0
- 4.3 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
OSVCLSA-2026-1787900734 No score
TuxCare security update for flask-cors (1 CVE)
TuxCare rebuilt flask-cors to address 1 CVE. Fixed in 4.0.2.post3+tuxcare.
- Record
CLSA-2026-1787900734- Updated
- 2026-11-02
OSVCLSA-2026-1789123062 No score
TuxCare security update for flask-cors (3 CVEs)
TuxCare rebuilt flask-cors to address 3 CVEs. Fixed in 5.0.1.post1+tuxcare.
- Record
CLSA-2026-1789123062- Updated
- 2026-11-02
OSVCLSA-2026-1789716215 No score
TuxCare security update for flask-cors (4 CVEs)
TuxCare rebuilt flask-cors to address 4 CVEs. Fixed in 3.0.10.post1+tuxcare.
- Record
CLSA-2026-1789716215- Updated
- 2026-11-02
OSVMGASA-2025-0286 No score
Updated python-flask-cors packages fix security vulnerabilities
Log Injection Vulnerability in corydolphin/flask-cors. (CVE-2024-1681) Improper Access Control in corydolphin/flask-cors. (CVE-2024-6221) Improper Regex Path Matching in corydolphin/flask-cors. (CVE-2024-6839) Inconsistent CORS Matching Due to Handling of '+' in URL Path in corydolphin/flask-cors. (CVE-2024-6844) Case-Insensitive Path Matching in corydolphin/flask-cors. (CVE-2024-6866)
- Record
MGASA-2025-0286- Updated
- 2026-11-02
OSVopenSUSE-SU-2026:10485-1 No score
python311-Flask-Cors-6.0.2-1.1 on GA media
These are all security issues fixed in the python311-Flask-Cors-6.0.2-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2026:10485-1- Updated
- 2026-11-02
OSVROOT-APP-PYPI-CVE-2024-6839 No score
CVE-2024-6839 in rootio-flask-cors - Patched by Root
Root has patched CVE-2024-6839 in the rootio-flask-cors package for Root:PyPI. Multiple fixed versions available.
- Record
ROOT-APP-PYPI-CVE-2024-6839- Updated
- 2026-11-02
OSVUSN-7612-1 No score
python-flask-cors vulnerabilities
It was discovered that Flask-CORS did not correctly handle certain regular expressions. A remote attacker could possibly use this issue to leak sensitive information or bypass authentication mechanisms. (CVE-2024-6839) It was discovered that Flask-CORS allowed certain CORS headers to be enabled by default. A remote attacker could possibly use this issue to leak sensitive information. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS, Ubuntu 24.04 LTS and Ubuntu 24.10. (CVE-2024-6221) It was discovered that Flask-CORS did not correctly handle case sensitivity when matching paths. A remote attacker could possibly use this issue to leak sensitive information. (CVE-2024-6866) It was discovered that Flask-CORS did not correctly handle certain characters in URL paths. A remote attacker could possibly use this issue to leak sensitive information or bypass authentication mechanisms. (CVE-2024-6844) Elias Hohl was discovered that Flask-CORS did not correctly sanitize log entries. A remote attacker could possibly use this issue to corrupt log files. This issue only affected Ubuntu 20.04 LTS, Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2024-1681)
- Record
USN-7612-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
flask-corsPyPI |
through 5.0.1 | 6.0.0 |
flask-corsTuxCare:PyPI |
4.0.2 up to 4.0.2.post3+tuxcare, plus listed versions 4.0.2.post1+tuxcare4.0.2.post2+tuxcare |
4.0.2.post3+tuxcare |
flask-corsTuxCare:PyPI From an advisory covering 3 CVEs |
5.0.1 up to 5.0.1.post1+tuxcare | 5.0.1.post1+tuxcare |
flask-corsTuxCare:PyPI From an advisory covering 4 CVEs |
3.0.10 up to 3.0.10.post1+tuxcare | 3.0.10.post1+tuxcare |
python-flask-corsDebian:12 |
before 3.0.10-2+deb12u1, plus listed versions 3.0.10-2 |
3.0.10-2+deb12u1 |
python-flask-corsDebian:13 |
before 6.0.1-1 | 6.0.1-1 |
python-flask-corsDebian:14 |
before 6.0.1-1 | 6.0.1-1 |
python-flask-corsDebian:11 From an advisory covering 4 CVEs |
before 3.0.9-2+deb11u1, plus listed versions 3.0.9-2 |
3.0.9-2+deb11u1 |
flask-corsPyPI |
before 6.0.0, plus listed versions 0.0.0.dev30.0.0.dev41.01.11.1.1 Show 45 moreShow less1.1.21.1.31.10.01.10.11.10.21.10.31.2.01.2.11.3.01.3.11.4.01.5.01.6.01.6.11.7.01.7.11.7.21.7.31.7.41.8.01.8.11.9.02.0.02.0.0rc12.0.12.1.02.1.12.1.22.1.33.0.03.0.13.0.103.0.23.0.33.0.43.0.63.0.73.0.83.0.94.0.04.0.0a04.0.14.0.25.0.05.0.1 |
6.0.0 |
python-flask-corsMageia:9 From an advisory covering 5 CVEs |
before 3.0.10-1.1.mga9 | 3.0.10-1.1.mga9 |
Show 11 moreShow less
| Package | Affected | Fixed |
|---|---|---|
python-Flask-CorsopenEuler:24.03-LTS From an advisory covering 3 CVEs |
before 6.0.1-1.oe2403 | 6.0.1-1.oe2403 |
python-Flask-CorsopenEuler:24.03-LTS-SP1 From an advisory covering 3 CVEs |
before 6.0.1-1.oe2403sp1 | 6.0.1-1.oe2403sp1 |
python-Flask-CorsopenEuler:24.03-LTS-SP2 From an advisory covering 3 CVEs |
before 6.0.1-1.oe2403sp2 | 6.0.1-1.oe2403sp2 |
rootio-flask-corsRoot:PyPI |
before 3.0.10+root.io.2 | 3.0.10+root.io.2 |
python-flask-corsUbuntu:Pro:20.04:LTS |
before 3.0.8-2ubuntu0.1+esm1, plus listed versions 3.0.8-23.0.8-2ubuntu0.1 |
3.0.8-2ubuntu0.1+esm1 |
python-flask-corsUbuntu:22.04:LTS |
before 3.0.9-2ubuntu0.1, plus listed versions 3.0.9-2 |
3.0.9-2ubuntu0.1 |
python-flask-corsUbuntu:Pro:24.04:LTS |
before 4.0.0-1ubuntu0.1~esm1, plus listed versions 4.0.0-1 |
4.0.0-1ubuntu0.1~esm1 |
python-flask-corsUbuntu:Pro:20.04:LTS From an advisory covering 5 CVEs |
before 3.0.8-2ubuntu0.1+esm1, plus listed versions 3.0.8-23.0.8-2ubuntu0.1 |
3.0.8-2ubuntu0.1+esm1 |
python-flask-corsUbuntu:22.04:LTS From an advisory covering 5 CVEs |
before 3.0.9-2ubuntu0.1, plus listed versions 3.0.9-2 |
3.0.9-2ubuntu0.1 |
python-flask-corsUbuntu:Pro:24.04:LTS From an advisory covering 5 CVEs |
before 4.0.0-1ubuntu0.1~esm1, plus listed versions 4.0.0-1 |
4.0.0-1ubuntu0.1~esm1 |
python-Flask-CorsopenSUSE:Tumbleweed From an advisory covering 3 CVEs |
before 6.0.2-1.1 | 6.0.2-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-6839 is a medium vulnerability (CVSS 4.3) in Corydolphin Corydolphin/flask-cors, published March 20, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.74%, the 54th percentile. Fixed in flask-cors 6.0.0.
References
huntr.com/bounties/403eb1fc-86f4-4820-8eba-0f3dfae9f2b4
lists.debian.org/debian-lts-announce/2025/05/msg00049.html
nvd.nist.gov/vuln/detail/CVE-2024-6839
github.com/corydolphin/flask-cors/commit/e970988bea563e05e8b8f53fa7bcc134b5bf5c5f
github.com/corydolphin/flask-cors/blob/4.0.1/flask_cors/core.py
github.com/advisories/GHSA-7rxf-gvfg-47g4
Show 21 moreShow less
github.com/CVEProject/cvelistV5/tree/main/cves/2024/6xxx/CVE-2024-6839.json
security-tracker.debian.org/tracker/CVE-2024-6839
github.com/corydolphin/flask-cors
advisories.mageia.org/MGASA-2025-0286.html
bugs.mageia.org/show_bug.cgi?id=34424
ubuntu.com/security/notices/USN-7612-1
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2025-1938
nvd.nist.gov/vuln/detail/CVE-2024-6844
nvd.nist.gov/vuln/detail/CVE-2024-6866
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2025-1939
openeuler.org/zh/security/security-bulletins/detail?id=openEuler-SA-2025-1981
pypi.org/project/flask-cors
ubuntu.com/security/CVE-2024-6839
cve.org/CVERecord?id=CVE-2024-6839
ubuntu.com/security/CVE-2024-1681
ubuntu.com/security/CVE-2024-6221
ubuntu.com/security/CVE-2024-6844
ubuntu.com/security/CVE-2024-6866
suse.com/security/cve/CVE-2024-6839
suse.com/security/cve/CVE-2024-6844
suse.com/security/cve/CVE-2024-6866