CVE-2026-3949
CVE-2026-3949 is a low-severity vulnerability with a CVSS 3.x base score of 3.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: Low (CVSS 3.x base score 3.3)
- CVSS v2: 1.7
- CVSS v4: 1.9
- EPSS exploit prediction: 0% (2nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-11300
- Weakness: CWE-119
- Published:
- Last modified:
Description
A vulnerability was determined in strukturag libheif up to 1.21.2. This affects the function vvdec_push_data2 of the file libheif/plugins/decoder_vvdec.cc of the component HEIF File Parser. Executing a manipulation of the argument size can lead to out-of-bounds read. The attack needs to be launched locally. The exploit has been publicly disclosed and may be utilized. This patch is called b97c8b5f198b27f375127cd597a35f2113544d03. It is advisable to implement a patch to correct this issue.
Frequently asked questions
- What is CVE-2026-3949?
- A vulnerability was determined in strukturag libheif up to 1.21.2. This affects the function vvdec_push_data2 of the file libheif/plugins/decoder_vvdec.cc of the component HEIF File Parser. Executing a manipulation of the argument size can lead to out-of-bounds read. The attack needs to be launched locally. The exploit has been publicly disclosed and may be utilized. This patch is called b97c8b5f198b27f375127cd597a35f2113544d03. It is advisable to implement a patch to correct this issue.
- How severe is CVE-2026-3949?
- CVE-2026-3949 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
- Is CVE-2026-3949 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-3949?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-3949 have an EU (EUVD) identifier?
- Yes. CVE-2026-3949 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11300.
- When was CVE-2026-3949 published?
- CVE-2026-3949 was published on 2026-03-11 and last updated on 2026-06-17.
References
- https://github.com/biniamf/pocs/tree/main/libheif_vvdec
- https://github.com/strukturag/libheif/
- https://github.com/strukturag/libheif/commit/b97c8b5f198b27f375127cd597a35f2113544d03
- https://github.com/strukturag/libheif/issues/1712
- https://github.com/strukturag/libheif/issues/1712#issuecomment-3947938531
- https://vuldb.com/?ctiid.350381
- https://vuldb.com/?id.350381
- https://vuldb.com/?submit.765979
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