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.
CVE-2026-26740
HIGHPre-NVD 8.28.2—
EchelonGraph scoreMEDIUM confidence
Score 8.2 from GitHub Security Advisory (severity: HIGH) published 2026-03-18. the CNA's CVSS baseline 8.2; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: cna:github_m, ghsa
8.2
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 8.2Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 8.2
- EG Score
- 8.2(medium)
- EPSS
- 45.3%
- KEV
- Not listed
Published
March 18, 2026
Last Modified
July 1, 2026
Advisory Details (4)
Auto-updated Jun 30, 2026🔬 Proof of concept available. Patch available. Sources: redhat.
redhat
Affected: Red Hat Enterprise Linux 10",
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26740.jsonredhat Patch Available
2448747 – (CVE-2026-26740) CVE-2026-26740 giflib: giflib: Denial of Service via buffer overflow in EGifGCBToExtension
https://bugzilla.redhat.com/show_bug.cgi?id=2448747generic🟡 PoC Available
POC/giflib/giftool/giflib_giftool_gce_len_heap_oobwrite_disclosure.md at main · zakkanijia/POC · GitHub
https://github.com/zakkanijia/POC/blob/main/giflib/giftool/giflib_giftool_gce_len_heap_oobwrite_disclosure.mdVendor Advisories for CVE-2026-26740(11)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:36006Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat AI Inference Server 3.2.2 (ROCm)
- RHSA-2026:36005Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat AI Inference Server 3.2.2 (CUDA)
- RHSA-2026:33503Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- RHSA-2026:33509Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- RHSA-2026:33456Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- RHSA-2026:33452Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- RHSA-2026:33455Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- RHSA-2026:33451Red Hat Product SecurityHigh
Red Hat Security Advisory: giflib security update
- +3 more
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 11× in last 7d / 13× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-05 02:30 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-01 15:06 UTCEPSS rescore
- 2026-07-01 15:06 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-30 04:31 UTCEG score recompute
- 2026-06-30 04:31 UTCGHSA enrichment
Related CVEs(same CWE)
Same CWE
10 shownCWE-787
- CVE-2007-0158EG 9.8CRITICAL
- CVE-2007-0899EG 9.8CRITICAL
- CVE-2011-2462EG 9.8 KEVEPSS 100%CRITICAL
- CVE-2010-20115EG 9.3CRITICAL
- CVE-2010-4398NVD 7.8EG 9.0 KEVEPSS 94%HIGH
- CVE-2010-3333NVD 7.8EG 9.0 KEVEPSS 100%HIGH
- CVE-2010-2883NVD 7.3EG 9.0 KEVEPSS 100%HIGH
- CVE-2010-1297NVD 7.8EG 9.0 KEVEPSS 100%HIGH
- CVE-2009-3953NVD 8.8EG 9.0 KEVEPSS 100%HIGH
- CVE-2009-3129NVD 7.8EG 9.0 KEVEPSS 100%HIGH
Frequently asked(5)
What is CVE-2026-26740?
CVE-2026-26740 is a high vulnerability published on March 18, 2026. 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.
When was CVE-2026-26740 disclosed?
CVE-2026-26740 was first published in the National Vulnerability Database on March 18, 2026, with the most recent update on July 1, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-26740 actively exploited?
CVE-2026-26740 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 45.3% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-26740?
CVE-2026-26740 has a CVSS v3.1 base score of 8.2 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-26740?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-26740, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-26740
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