Integer overflow in Lighttpd
CVE-2019-11072
lighttpd before 1.4.54 has a signed integer overflow, which might allow remote attackers to cause a denial of service (application crash) or possibly have unspecified other impact via a malicious HTTP GET request, as demonstrated by mishandling of /%2F? in burl_normalize_2F_to_slash_fix in burl.c. NOTE: The developer states "The feature which can be abused to cause the crash is a new feature in lighttpd 1.4.50, and is not enabled by default. It must be explicitly configured in the config file (e.g. lighttpd.conf). Certain input will trigger an abort() in lighttpd when that feature is enabled. lighttpd detects the underflow or realloc() will fail (in both 32-bit and 64-bit executables), also detected in lighttpd. Either triggers an explicit abort() by lighttpd. This is not exploitable beyond triggering the explicit abort() with subsequent application exit.
Vulnerability class: Integer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.738 (99.5th percentile), scored .
High probability of exploitation in the next 30 days — patch promptly. 99th percentile — 99.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.738 · newest: 0.738 · change: 0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- redmine.lighttpd.net/issues/2945 (Exploit, Patch, Third Party Advisory)
- github.com/lighttpd/lighttpd1.4/commit/32120d5b8b3203fc21ccb9eafb0eaf824bb59354 (Patch, Third Party Advisory)
- www.securityfocus.com/bid/107907 (VDB Entry, Third Party Advisory, vdb-entry)
Frequently asked questions
- What is CVE-2019-11072?
- CVE-2019-11072 is a critical-severity vulnerability in Lighttpd, classified under Integer Overflow or Wraparound. CVSS score: 9.8/10. Published 2019-04-10.
- How severe is CVE-2019-11072?
- Critical severity. CVSS v3 base score is 9.8 out of 10.
- Is CVE-2019-11072 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.