CVE-2019-17266

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-10-06 · updated 2026-06-17
Weakness: CWE-125

Description

libsoup from versions 2.65.1 until 2.68.1 have a heap-based buffer over-read because soup_ntlm_parse_challenge() in soup-auth-ntlm.c does not properly check an NTLM message's length before proceeding with a memcpy.

Affected products

Canonical Ubuntu Linux: 18.04, 19.04
GNOME libsoup: from 2.65.1 before 2.66.4; from 2.67.1 through 2.68.1 — fixed in 2.66.4

How to fix

Upgrade to a fixed version: GNOME libsoup 2.66.4. Check the vendor advisory for mitigations.

References

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=941912
https://github.com/Kirin-say/Vulnerabilities/blob/master/CVE-2019-17266_POC.md
https://gitlab.gnome.org/GNOME/libsoup/commit/88b7dff4467f4151afae244ea7d1223753cd05ab
https://gitlab.gnome.org/GNOME/libsoup/commit/f8a54ac85eec2008c85393f331cdd251af8266ad
https://gitlab.gnome.org/GNOME/libsoup/issues/173
https://security-tracker.debian.org/tracker/CVE-2019-17266
https://usn.ubuntu.com/4152-1/
https://www.mail-archive.com/debian-bugs-dist%40lists.debian.org/msg1705054.html
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=941912
https://github.com/Kirin-say/Vulnerabilities/blob/master/CVE-2019-17266_POC.md
https://gitlab.gnome.org/GNOME/libsoup/commit/88b7dff4467f4151afae244ea7d1223753cd05ab
https://gitlab.gnome.org/GNOME/libsoup/commit/f8a54ac85eec2008c85393f331cdd251af8266ad

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