Vulnerability in Ewen-Lbh Ffcss
CVE-2023-52081
ffcss is a CLI interface to apply and configure Firefox CSS themes. Prior to 0.2.0, the function `lookupPreprocess()` is meant to apply some transformations to a string by disabling characters in the regex `[-_ .]`. However, due to the use of late Unicode normalization of type NFKD, it is possible to bypass that validation and re-introduce all the characters in the regex `[-_ .]`. The `lookupPreprocess()` can be easily bypassed with equivalent Unicode characters like U+FE4D (﹍), which would result in the omitted U+005F (_), for instance. The `lookupPreprocess()` function is only ever used to search for themes loosely (case insensitively, while ignoring dashes, underscores and dots), so the actual security impact is classified as low. This vulnerability is fixed in 0.2.0. There are no known workarounds.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.005 (43.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 43rd percentile — 43.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Ewen-Lbh Ffcss — versions < 0.2.0
- Ewen-Lbh Firefox CSS
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/ewen-lbh/ffcss/security/advisories/GHSA-wpmx-564x-h2mh (Exploit, Vendor Advisory)
- github.com/ewen-lbh/ffcss/commit/f9c491874b858a32fcae15045f169fd7d02f90dc (Patch)
Frequently asked questions
- What is CVE-2023-52081?
- CVE-2023-52081 is a medium-severity vulnerability in Ewen-Lbh Ffcss, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 5.3/10. Published 2023-12-28.
- How severe is CVE-2023-52081?
- Medium severity. CVSS v3 base score is 5.3 out of 10.
- Is CVE-2023-52081 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.