5.3

CVE-2026-77014: libsoup2.4 Numeric Truncation Error

CVSS: 5.3v3.1MediumAwaiting analysis
AliasesUBUNTU-CVE-2026-77014DEBIAN-CVE-2026-77014
Published 20-08-2026Last modified 25-08-2026
Open JSON

Vulnerability summary

CVE-2026-77014 is a medium (CVSS 5.3) Numeric Truncation Error vulnerability in libsoup2.4. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 13.2% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.23%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 3
OPENSUSE-SU-2026:11860-1SUSE-SU-2026:4703-1USN-8890-1

Timeline

  1. 20-08-2026
    PublishedVulnerability first disclosed.
  2. 25-08-2026
    Last modifiedVulnerability information updated.

Description

A flaw was found in libsoup's SoupServer HTTP Range header processing. The sort_ranges() comparator in soup-message-headers.c truncates a 64-bit subtraction result to 32-bit int, flipping the sign for range offsets differing by more than INT_MAX. This causes silent omission of requested byte ranges from HTTP 206 Partial Content responses on resources larger than approximately 2 GB.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

0.00 pp

From 0.23% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.23%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian2 products
  • libsoup2.4All versions (No fix recorded)
  • libsoup3All versions (No fix recorded) | < 3.8.0-1
Ubuntu2 products
  • libsoup2.4< 2.52.2-1ubuntu0.3+esm8 | < 2.62.1-1ubuntu0.4+esm9 | < 2.70.0-1ubuntu0.5+esm4 | < 2.74.2-3ubuntu0.9 | < 2.74.3-6ubuntu1.9 | All versions (No fix recorded) | < 2.74.3-10.1ubuntu5+esm3
  • libsoup3< 3.0.7-0ubuntu1+esm9 | < 3.4.4-5ubuntu0.9 | All versions (No fix recorded) | < 3.6.6-1ubuntu0.1

2 vendors · 4 products

References

7 links