CVE-2021-45909
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in...
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
CVE-2021-45909- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.8 Medium
AV:N/AC:M/Au:N/C:P/I:P/A:P - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List No score
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
CVE-2021-45909- Updated
- 2026-11-02
EUVDEUVD-2021-32624 No score
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
EUVD-2021-32624- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-c9fh-qp5h-24w7
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in...
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
GHSA-c9fh-qp5h-24w7- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
OSV
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
CVE-2021-45909- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVDEBIAN-CVE-2021-45909
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
DEBIAN-CVE-2021-45909- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-45909
An issue was discovered in gif2apng 1.9. There is a heap-based buffer overflow vulnerability in the DecodeLZW function. It allows an attacker to write a large amount of arbitrary data outside the boundaries of a buffer.
- Record
UBUNTU-CVE-2021-45909- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUSN-5969-1 No score
gif2apng vulnerabilities
It was discovered that gif2apng contained multiple heap-base overflows. An attacker could potentially exploit this to cause a denial of service (system crash). (CVE-2021-45909, CVE-2021-45910, CVE-2021-45911)
- Record
USN-5969-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gif2apngDebian:11 |
before 1.9+srconly-3+deb11u1, plus listed versions 1.9+srconly-3 |
1.9+srconly-3+deb11u1 |
gif2apngDebian:9 From an advisory covering 3 CVEs |
before 1.9+srconly-2+deb9u2, plus listed versions 1.9+srconly-21.9+srconly-2+deb9u1 |
1.9+srconly-2+deb9u2 |
gif2apngUbuntu:Pro:16.04:LTS |
before 1.7-3ubuntu0.1~esm1, plus listed versions 1.7-3 |
1.7-3ubuntu0.1~esm1 |
gif2apngUbuntu:18.04:LTS |
before 1.9+srconly-2ubuntu0.1, plus listed versions 1.9+srconly-2 |
1.9+srconly-2ubuntu0.1 |
gif2apngUbuntu:20.04:LTS |
before 1.9+srconly-3ubuntu0.1, plus listed versions 1.9+srconly-31.9+srconly-3build1 |
1.9+srconly-3ubuntu0.1 |
gif2apngUbuntu:Pro:16.04:LTS From an advisory covering 3 CVEs |
before 1.7-3ubuntu0.1~esm1, plus listed versions 1.7-3 |
1.7-3ubuntu0.1~esm1 |
gif2apngUbuntu:18.04:LTS From an advisory covering 3 CVEs |
before 1.9+srconly-2ubuntu0.1, plus listed versions 1.9+srconly-2 |
1.9+srconly-2ubuntu0.1 |
gif2apngUbuntu:20.04:LTS From an advisory covering 3 CVEs |
before 1.9+srconly-3ubuntu0.1, plus listed versions 1.9+srconly-31.9+srconly-3build1 |
1.9+srconly-3ubuntu0.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-45909 is a high vulnerability (CVSS 7.8) in Gif2apng Project Gif2apng, published December 28, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.90%, the 59th percentile. Fixed in gif2apng 1.9+srconly-3+deb11u1.