CVE-2021-20240
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out...
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
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
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 2.0
- 8.3 High
AV:N/AC:M/Au:N/C:P/I:P/A:C - Weakness
- CWE-191
- Updated
- 2026-11-02
CVE List No score
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
CVE-2021-20240- Weakness
- CWE-191
- Updated
- 2026-11-02
EUVDEUVD-2021-7679 No score
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
EUVD-2021-7679- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-cjqx-m2ff-vgj5
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out...
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
GHSA-cjqx-m2ff-vgj5- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-191, CWE-787
- Updated
- 2026-11-02
OSVALPINE-CVE-2021-20240
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
ALPINE-CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVBELL-CVE-2021-20240
8.8
CVE-2021-20240 does not affect BellSoft software
- Record
BELL-CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
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OSV
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-04
OSVDEBIAN-CVE-2021-20240
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
DEBIAN-CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVOESA-2022-1762
8.8
gdk-pixbuf2 security update
gdk is written in C but has been designed from the ground up to support a wide range of languages. It provide a complete set of widgets,and suitable for projects ranging from small one-off tools to complete application suites.
Security Fix(es):
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.(CVE-2021-20240)
GNOME gdk-pixbuf (aka GdkPixbuf) before 2.42.2 allows a denial of service (infinite loop) in lzw.c in the function write_indexes. if c->self_code equals 10, self->code_table[10].extends will assign the value 11 to c. The next execution in the loop will assign self->code_table[11].extends to c, which will give the value of 10. This will make the loop run infinitely. This bug can, for example, be triggered by calling this function with a GIF image with LZW compression that is crafted in a special way.(CVE-2020-29385)
- Record
OESA-2022-1762- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-20240
8.8
A flaw was found in gdk-pixbuf in versions before 2.42.0. An integer wraparound leading to an out of bounds write can occur when a crafted GIF image is loaded. An attacker may cause applications to crash or could potentially execute code on the victim system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
- Record
UBUNTU-CVE-2021-20240- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUSN-4743-1 No score
gdk-pixbuf vulnerability
It was discovered that the GDK-PixBuf library did not properly handle certain GIF images. If an user or automated system were tricked into opening a specially crafted GIF file, a remote attacker could use this flaw to cause GDK-PixBuf to crash, resulting in a denial of service.
- Record
USN-4743-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
gdk-pixbufAlpine:v3.11 |
before 2.40.0-r1 | 2.40.0-r1 |
gdk-pixbufAlpine:v3.12 |
before 2.40.0-r3 | 2.40.0-r3 |
gdk-pixbufDebian:12 |
before 2.42.2+dfsg-1 | 2.42.2+dfsg-1 |
gdk-pixbufDebian:13 |
before 2.42.2+dfsg-1 | 2.42.2+dfsg-1 |
gdk-pixbufDebian:14 |
before 2.42.2+dfsg-1 | 2.42.2+dfsg-1 |
gdk-pixbuf2openEuler:20.03-LTS-SP3 From an advisory covering 2 CVEs |
before 2.40.0-2.oe1 | 2.40.0-2.oe1 |
gdk-pixbufUbuntu:20.04:LTS |
before 2.40.0+dfsg-3ubuntu0.2, plus listed versions 2.40.0+dfsg-1build12.40.0+dfsg-1ubuntu12.40.0+dfsg-22.40.0+dfsg-32.40.0+dfsg-3ubuntu0.1 |
2.40.0+dfsg-3ubuntu0.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected | ||
| facts | OSV | |
| aliases | EUVD, OSV | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20240 is a high vulnerability (CVSS 8.8) in Gnome Gdk-pixbuf, published February 17, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.35%, the 83rd percentile. Fixed in gdk-pixbuf 2.40.0-r1.
References
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/EANWYODLOJDFLMBH6WEKJJMQ5PKLEWML
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B5H3GNVWMZTYZR3JBYCK57PF7PFMQBNP
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BGZVCTH5O7WBJLYXZ2UOKLYNIFPVR55D
bugzilla.redhat.com/show_bug.cgi?id=1926787
nvd.nist.gov/vuln/detail/CVE-2021-20240
lists.fedoraproject.org/archives/list/[email protected]/message/B5H3GNVWMZTYZR3JBYCK57PF7PFMQBNP
Show 11 moreShow less
lists.fedoraproject.org/archives/list/[email protected]/message/BGZVCTH5O7WBJLYXZ2UOKLYNIFPVR55D
lists.fedoraproject.org/archives/list/[email protected]/message/EANWYODLOJDFLMBH6WEKJJMQ5PKLEWML
github.com/advisories/GHSA-cjqx-m2ff-vgj5
security.alpinelinux.org/vuln/CVE-2021-20240
docs.bell-sw.com/security/cves/CVE-2021-20240
security-tracker.debian.org/tracker/CVE-2021-20240
openeuler.org/en/security/safety-bulletin/detail.html?id=openEuler-SA-2022-1762
nvd.nist.gov/vuln/detail/CVE-2020-29385
ubuntu.com/security/CVE-2021-20240
ubuntu.com/security/notices/USN-4743-1
cve.org/CVERecord?id=CVE-2021-20240