What is CVE-2020-23904?

CVE-2020-23904 is a medium-severity vulnerability in Xiph Speex, classified under Out-of-bounds Write. CVSS score: 5.5/10. Published 2021-11-10.

How severe is CVE-2020-23904?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Is CVE-2020-23904 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Xiph Speex

CVE-2020-23904

A stack buffer overflow in speexenc.c of Speex v1.2 allows attackers to cause a denial of service (DoS) via a crafted WAV file. NOTE: the vendor states "I cannot reproduce it" and it "is a demo program.

Vulnerability class: Buffer Overflow

Published 2021-11-10 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.007 (53.4th percentile), scored 2026-10-24.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Xiph Speex — versions 1.2

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

github.com/xiph/speex/issues/14 (Exploit, Third Party Advisory, Issue Tracking)

Frequently asked questions

What is CVE-2020-23904?: CVE-2020-23904 is a medium-severity vulnerability in Xiph Speex, classified under Out-of-bounds Write. CVSS score: 5.5/10. Published 2021-11-10.
How severe is CVE-2020-23904?: Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2020-23904 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.