Giflib 5.2.2 EGifGCBToExtension buffer overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Giflib 5.2.2. It has been rated as critical. The impacted element is the function EGifGCBToExtension. This manipulation causes buffer overflow. The identification of this vulnerability is CVE-2026-26740. It is possible to initiate the attack remotely. Furthermore, there is an exploit available.

Detailsinfo

A vulnerability has been found in Giflib 5.2.2 and classified as critical. Affected by this vulnerability is the function EGifGCBToExtension. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

Buffer Overflow vulnerability in giflib v.5.2.2 allows a remote attacker to cause a denial of service via the EGifGCBToExtension overwriting an existing Graphic Control Extension block without validating its allocated size.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-26740 since 02/16/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details and also a public exploit are known.

It is possible to download the exploit at github.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 309659 (RHEL 7 / 8 / 9 : Java 11 OpenJDK ELS Security Update (Important) (RHSA-2026:9254)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (309659), EUVD (EUVD-2026-12914) and CERT Bund (WID-SEC-2026-2137). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Red Hat Enterprise Linux
  • SUSE Linux
  • Oracle Linux
  • RESF Rocky Linux

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.2
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 8.2
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 309659
Nessus Name: RHEL 7 / 8 / 9 : Java 11 OpenJDK ELS Security Update (Important) (RHSA-2026:9254)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

02/16/2026 CVE reserved
03/18/2026 +30 days Advisory disclosed
03/18/2026 +0 days VulDB entry created
07/02/2026 +106 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2026-26740 (🔒)
GCVE (CVE): GCVE-0-2026-26740
GCVE (VulDB): GCVE-100-351589
EUVD: 🔒
CERT Bund: WID-SEC-2026-2137 - Red Hat Enterprise Linux (giflib): Schwachstelle ermöglicht Denial of Service

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/18/2026 19:58
Updated: 07/02/2026 15:00
Changes: 03/18/2026 19:58 (55), 03/18/2026 20:58 (1), 03/22/2026 13:04 (11), 03/24/2026 18:55 (1), 04/23/2026 02:33 (2), 07/02/2026 15:00 (7)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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