CVE-2026-1940 | Gstreamer: incomplete fix of cve-2026-1940

An incomplete fix for CVE-2024-47778 allows an out-of-bounds read in gst_wavparse_adtl_chunk() function. The patch added a size validation check lsize + 8 > size, but it does not account for the GST_ROUND_UP_2(lsize) used in the actual offset calculation. When lsize is an odd number, the parser advances more bytes than validated, causing OOB read.

Published: 2026-03-23 Last update: 2026-05-04 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-1940 is rated Low Risk (25.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.22%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-1940

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.22% +0.17%
2 2026-05-13 0.01% 0.05% +0.04%
3 2026-03-24 0.01%

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-1940

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.1 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
2.5 2.5 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-1940

OS Trackers for CVE-2026-1940

vendor priority summary link
debian not yet assigned CVE-2026-1940 not yet assigned priority: Debian including 1 source packages (gst-plugins-good1.0), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 3, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-1940
redhat medium https://access.redhat.com/security/cve/CVE-2026-1940
suse medium https://www.suse.com/security/cve/CVE-2026-1940/
ubuntu medium CVE-2026-1940 medium priority: Ubuntu including 1 source packages (gst-plugins-bad1.0), 8 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): needs-triage 7, released 1. https://ubuntu.com/security/CVE-2026-1940

Affected software / configurations for CVE-2026-1940

Vendor Product Version Raw CPE
freedesktop gst-plugins-good 1.0.0 cpe:2.3:a:freedesktop:gst-plugins-good:1.0.0:*:*:*:*:*:*:*
gstreamer gstreamer < 1.28.1 cpe:2.3:a:gstreamer:gstreamer:*:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
debian debian_linux 12.0 cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*
redhat enterprise_linux 7.0 cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
redhat enterprise_linux 10.0 cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*

References for CVE-2026-1940

cvelogic Threat Intelligence