CVE-2026-3950

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.12% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 2.0% of scored records. A rank, not a probability.

NVD base score

1.9 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-06-17.

Red Hat severity

Low. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-03-11 19:02Z5 MO AGO

Last updated

2026-03-11 20:24Z5 MO AGO

Reserved

2026-03-11

Assigning CNA

VulDB

Record state

PUBLISHED

Severity

Medium (CVSS 4.8)

CNA CVSS vector

CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P

Weaknesses

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass
• CWE-125Out-of-bounds ReadBase

Data version

5.2

Document digest

1a99f16a0324b6531a1757043d245c2a092df17ff28463efb53bb0a5530c7915

• vuldb.comVDB-350382 | strukturag libheif stsz/stts track.cc load out-of-boundshttps://vuldb.com/?id.350382vdb-entrytechnical-description
• vuldb.comVDB-350382 | CTI Indicators (IOB, IOC, IOA)https://vuldb.com/?ctiid.350382signaturepermissions-required
• vuldb.comSubmit #766431 | strukturag libheif 1.21.2 Out-of-Bounds Readhttps://vuldb.com/?submit.766431third-party-advisory
• github.comhttps://github.com/strukturag/libheif/issues/1715issue-tracking
• github.comhttps://github.com/Niebelungen-D/pocs/tree/main/heif_dec_sequence_chunk_idx_oobexploit
• github.comhttps://github.com/strukturag/libheif/pull/1721issue-trackingpatch
• github.comhttps://github.com/strukturag/libheif/product