Auth bypass in Lilypond
CVE-2020-17354
LilyPond before 2.24 allows attackers to bypass the -dsafe protection mechanism via output-def-lookup or output-def-scope, as demonstrated by dangerous Scheme code in a .ly file that causes arbitrary code execution during conversion to a different file format. NOTE: in 2.24 and later versions, safe mode is removed, and the product no longer tries to block code execution when external files are used.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.004 (33.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 33rd percentile — 33.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
Weakness classification (CWE)
References
- lilypond.org/doc/v2.18/Documentation/usage/command_002dline-usage (Release Notes)
- phabricator.wikimedia.org/T259210 (Exploit, Third Party Advisory)
- www.mediawiki.org/wiki/Extension:Score/2021_security_advisory (Third Party Advisory)
- tracker.debian.org/news/1249694/accepted-lilypond-2221-1-source-into-unstable/ (Mailing List, Third Party Advisory, Release Notes)
- gitlab.com/lilypond/lilypond/-/merge_requests/1522 (Patch, Vendor Advisory)
- lilypond.org/download.html (Product)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2020-17354?
- CVE-2020-17354 is a high-severity vulnerability in Lilypond, classified under Incorrect Authorization. CVSS score: 8.6/10. Published 2023-04-15.
- How severe is CVE-2020-17354?
- High severity. CVSS v3 base score is 8.6 out of 10.