CVE-2021-35516
No exploitation reported by the sources we read.
- Published2021-07-13
- WeaknessCWE-130 · CWE-770
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
When reading a specially crafted 7Z archive, Compress can be made to allocate large amounts of memory that finally leads to an out of memory error even for very small inputs. This could be used to mount a denial of service attack against services that use Compress' sevenz package.
Timeline
dates in UTC- 2021-07-1308:15CVE publishedNVD
- 2026-10-2319:23EPSS crossed 10 %FIRST EPSS
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-35516?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-35516?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 18.x | ≥ 18.1, ≤ 18.3 | no fix published | NVD |
| 19.1 | = 19.1 | no fix published | NVD |
| 19.2 | = 19.2 | no fix published | NVD |
| 20.1 | = 20.1 | no fix published | NVD |
| 21.1 | = 21.1 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 11.0 | = 11.0.2 | no fix published | NVD |
| 11.1 | = 11.1.0 | no fix published | NVD |
| 11.2 | = 11.2.8 | no fix published | NVD |
| 11.3 | = 11.3.0 | no fix published | NVD |
| 11.3 | = 11.3.1 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 17.x | ≥ 17.7, ≤ 17.12 | no fix published | NVD |
| 18.8 | = 18.8 | no fix published | NVD |
| 19.12 | = 19.12 | no fix published | NVD |
| 20.12 | = 20.12 | no fix published | NVD |
21 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- commons.apache.orgVendor Advisory
- lists.apache.orgVendor Advisory
- www.oracle.comPatch
- www.oracle.comPatch
- www.oracle.comPatch
- 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 3.17.5read 2026-10-23
- NVDCVSS 2.05read 2026-10-23
- CNAweakness (CWE)CWE-130read 2026-10-23
- NVDweakness (CWE)CWE-770read 2026-10-23
- FIRST EPSSEPSS score12.4 %read 2026-10-23
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Published
- 2021-07-13
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-35516?
Is CVE-2021-35516 actively exploited?
What is the CVSS score for CVE-2021-35516?
Hear about the next vulnerability in your software
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
No credit card required · No monthly cap on website lookups · 250 API requests/month
Go further
- Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
- Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.
Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.