libde265 has an unbounded memory leak via orphaned slice headers in `read_slice_NAL`

Description

libde265 is an open source implementation of the h.265 video codec. Prior to version 1.0.20, a crafted sequence of H.265 NAL units causes `decoder_context::read_slice_NAL()` (`libde265/decctx.cc:481`) to attach slice headers to a finished picture object that has no active image unit, resulting in attacker-controlled unbounded heap growth. The retained headers are never freed until the picture is released, which may not happen during continuous streaming. Version 1.0.20 patches the issue.

Scores

EPSS (exploitation in 30 days)

0.24% · top 85% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.

Weakness

• CWE-770: Allocation of Resources Without Limits or Throttling (opens in a new tab)All about CWE-770 and its CVEs

Affected products

• strukturag · libde265

  • affected < 1.0.20

References (2)

• https://github.com/strukturag/libde265/security/advisories/GHSA-g5hj-rf9f-7vxm (opens in a new tab)x_refsource_CONFIRMexploit
• https://github.com/strukturag/libde265/commit/683cb9fa603e35840642f98765ab95cdb71cadf9 (opens in a new tab)x_refsource_MISC

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-49337](https://trackcve.app/badge/CVE-2026-49337.svg)](https://trackcve.app/cve/CVE-2026-49337)

Record last updated 22 Jun 2026, 14:00 UTC.