Undefined behavior via off-by-one OpusTags buffer access
Published Jan 15, 2026 · Updated Jan 15, 2026
Out-of-bounds access in GPAC 2.4.0 OGG demuxer allows attackers to trigger undefined behavior by processing crafted OpusTags metadata. oggdmx_parse_tags accepts an attacker-controlled t_size equal to the remaining buffer size, then reads data[t_size], writes a NUL byte there, and restores it, touching one byte beyond the valid range. Reachability requires GPAC to parse crafted OGG OpusTags metadata; the demonstrated write is transient, while a process crash depends on memory layout.
Summary
What happened
Out-of-bounds access in GPAC 2.4.0 OGG demuxer allows attackers to trigger undefined behavior by processing crafted OpusTags metadata. oggdmx_parse_tags accepts an attacker-controlled t_size equal to the remaining buffer size, then reads data[t_size], writes a NUL byte there, and restores it, touching one byte beyond the valid range. Reachability requires GPAC to parse crafted OGG OpusTags metadata; the demonstrated write is transient, while a process crash depends on memory layout.
The record
- CVE
- CVE-2025-70298
- Published
- Jan 15, 2026
- Updated
- Jan 15, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-125
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jan 15, 2026CVE publishedPublication date reported by the CVE source.
- Jan 15, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- GPAC OGG demuxer off-by-one proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo