CVE-2021-35940
No exploitation reported by the sources we read.
- Published2021-08-23
- Fixed in1.7.1
- WeaknessCWE-125
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
An out-of-bounds array read in the apr_time_exp*() functions was fixed in the Apache Portable Runtime 1.6.3 release (CVE-2017-12613). The fix for this issue was not carried forward to the APR 1.7.x branch, and hence version 1.7.0 regressed compared to 1.6.3 and is vulnerable to the same issue.
Timeline
dates in UTC- 2021-08-2310:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-35940?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-35940?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
OSV · NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 1.7 | ≥ 1.7.0, < 1.7.1 | 1.7.1 | OSV |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 12.2 | = 12.2.1.3.0 | no fix published | NVD |
| 12.2 | = 12.2.1.4.0 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 1.7 | = 1.7.0 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
Rockwell Automation FactoryTalk Edge Gateway
FactoryTalk Edge Gateway: v1.3
Fix
- Update apr to 1.7.1
- Vendor fix CISA ICSA-23-164-03 · 1 productRockwell Automation encourages users of the affected software to apply the risk mitigation below, if possible. Additionally, they encourage users to implement their suggested security best practices to minimize the risk.
- Vendor fix CISA ICSA-23-164-03 · 1 productUpdate to v1.4
- Vendor fix CISA ICSA-23-164-03 · 1 productSecurity Best Practices
- Vendor fix CISA ICSA-23-164-03 · 1 productPlease see the Rockwell Automation publication regarding this issue for more information.
Advisories and patches
- svn.apache.orgVendor Advisory
- dist.apache.orgPatch · Vendor Advisory
- lists.apache.orgVendor Advisory
- www.oracle.comPatch
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.17.1read 2026-10-23
- NVDCVSS 2.03.6read 2026-10-23
- NVDweakness (CWE)CWE-125read 2026-10-23
- FIRST EPSSEPSS score1.2 %2026-10-23
- OSVaffected packages—
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
- Published
- 2021-08-23
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-35940?
Is CVE-2021-35940 actively exploited?
What is the CVSS score for CVE-2021-35940?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.