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Evidence dossier
CVE-2021-42013
Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)
78.7–99.5Priority evidence range
gen-56ccdaf9Normalized restatement
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.
- State
- PUBLISHED
- Published
- Oct 7, 2021
- Updated
- Oct 21, 2025
- Evidence coverage
- 72%
2026-07-18 · v2026.06.15 · percentile 100.0%
Distinct CVSS assessments remain side by side; none are averaged.
Source comparison
Who said what
apacheoriginal assertion
container
Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)
Jul 19, 2026Original evidence ↗
CISA KEVoriginal assertion
observed_exploitation
Apache HTTP Server Path Traversal Vulnerability
Jul 19, 2026Original evidence ↗
FIRST EPSSoriginal assertion
model_probability
Probability 0.999640000000; percentile 0.999760000000
Jul 19, 2026Original evidence ↗
Applicability
Cited product scope
Apache Software FoundationApache HTTP Server
[{"status": "affected", "version": "Apache HTTP Server 2.4.49"}, {"status": "affected", "version": "Apache HTTP Server 2.4.50"}]unknownUnknown vendorUnknown product
cpe:2.3:a:apache:http_server:2.4.49:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:apache:http_server:2.4.50:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:oracle:instantis_enterprisetrack:17.1:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:oracle:instantis_enterprisetrack:17.2:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:oracle:instantis_enterprisetrack:17.3:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:a:oracle:jd_edwards_enterpriseone_tools:*:*:*:*:*:*:*:*; end excluding 9.2.6.0supportedUnknown vendorUnknown product
cpe:2.3:a:oracle:secure_backup:*:*:*:*:*:*:*:*; end excluding 18.1.0.1.0supportedUnknown vendorUnknown product
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*supportedUnknown vendorUnknown product
cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*supportedAssessments
CVSS by origin
nvd@nist.govCVSS 3.1 · role Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hnvd@nist.govCVSS 2.0 · role Primary
AV:N/AC:L/Au:N/C:P/I:P/A:P134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCISA-ADPCVSS 3.1 · role unknown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLimitations and unknowns
- KEV membership is authoritative for the catalog, not proof of exposure in any environment.
- EPSS is a dated model probability and not an individual-environment prediction.
- Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
- NVD-carried upstream facts remain derivative and are not independent corroboration.
- Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
- NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
- Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
- Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.