Cyber Resilience

CVE-2024-56431

CriticalPublic PoC

Published: 25 December 2024

Published
25 December 2024
Modified
25 April 2025
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.1436 94.6th percentile
Risk Priority 28 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-56431 is a critical-severity Incorrect Authorization (CWE-863) vulnerability in Xiph Theora. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 5.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

The vulnerability is an invalid negative left shift in the oc_huff_tree_unpack function within huffdec.c of libtheora, affecting Theora releases through version 1.0 at commit 7180717. It is tracked as CVE-2024-56431 with a CVSS 3.1 score of 9.8 and is associated with CWE-863, though multiple third parties have disputed any actual security impact on the grounds that no application crash or other observable effect has been demonstrated.

An unauthenticated remote attacker can supply a specially crafted Theora stream or file to trigger the flaw over a network connection. Successful exploitation could result in full confidentiality, integrity, and availability compromise according to the CVSS vector, although the disputed status indicates that practical attack outcomes remain unconfirmed.

Public references include a proof-of-concept repository, the upstream source line, a GitHub issue discussion, and oss-security mailing list threads from April 2025 that examine the report. No vendor patches or explicit mitigation steps are documented in the available references. The associated EPSS score has reached a peak of 0.1491 with a current value of 0.1436, indicating moderate and relatively stable exploitation interest since disclosure.

EU & UK References

Vulnerability details

oc_huff_tree_unpack in huffdec.c in libtheora in Theora through 1.0 7180717 has an invalid negative left shift. NOTE: this is disputed by third parties because there is no evidence of a security impact, e.g., an application would not crash.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

xiph
theora
≤ 1.2.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-863

Periodic review and update of procedures reduces incorrect authorization implementations over time.

addresses: CWE-863

Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.

addresses: CWE-863

Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.

addresses: CWE-863

The authorization process and usage restrictions help prevent incorrect authorization for remote access types.

addresses: CWE-863

Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.

addresses: CWE-863

Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.

addresses: CWE-863

Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.

addresses: CWE-863

Ensures authorization decisions for external system use are correctly implemented and enforced.

References