CVE intelligence and bounded remediation
CVE-2021-26843 — An issue was discovered in sthttpd through 2.27.1
An issue was discovered in sthttpd through 2.27.1. On systems where the strcpy function is implemented with memcpy, the de_dotdot function may cause a Denial-of-Service (daemon crash) due to overlapping memory ranges being passed to memcpy. This can triggered with an HTTP GET request for a crafted filename. NOTE: this is similar to CVE-2017-10671, but occurs in a different part of the de_dotdot function.
- Severity
- High
- CVSS
- 7.5 (3.1)
- Published
- 2021-02-07
- CISA KEV
- Not currently listed
- Ecosystem
- software/application
- Weaknesses
- CWE-119
Affected products
- sthttpd_project / sthttpd
Matched remediation archetype
Buffer bounds, memory safety, and memory corruption
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
- Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
- Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.
Remediate safely
- Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
- Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
- Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.
Authoritative sources
Complete CVE record and remediation plan
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