CVE Intelligence
High Denial of service

CVE-2021-35517 — Apache Commons Compress 1.1 to 1.20 denial of service vulnerability

When reading a specially crafted TAR 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' tar package.

Published Jul 13, 2021 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: apache

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 10.6% (30-day exploitation probability)+14
  • Technical severity (high)+6
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
10.61%
ahead of 96% of scored CVEs · Oct 14, 2026
Affects
Apache Software Foundation
Commons Compress and 26 more
CVSS base
7.5
High · 1 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)
  • Documented patch — www.oracle.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Apache Software Foundation Commons Compress, Netapp Active Iq Unified Manager, Netapp Oncommand Insight…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. EPSS ahead of 96% of scored CVEs: prioritize it in the patch queue.
  5. Search available logs for exploit probes matching the vulnerability class (denial of service), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Apache Software Foundation Commons Compress ≥ 1.1 and < Apache Commons Compress* Vulnerable CVE Program (cve.org) e CISA ADP
Apache Software Foundation Commons Compress ≥ 1.1 and ≤ 1.20 Vulnerable NIST National Vulnerability Database
Netapp Active Iq Unified Manager versions not specified by the source Vulnerable NIST National Vulnerability Database
Netapp Oncommand Insight versions not specified by the source Vulnerable NIST National Vulnerability Database
Oracle Banking Apis ≥ 18.1 and ≤ 18.3version 21.1version 20.1version 19.2version 19.1 Vulnerable NIST National Vulnerability Database
Oracle Banking Digital Experience ≥ 18.1 and ≤ 18.3version 21.1version 20.1version 19.2version 19.1 Vulnerable NIST National Vulnerability Database
Oracle Banking Enterprise Default Management version 2.7.0 Vulnerable NIST National Vulnerability Database
Oracle Banking Party Management version 2.7.0 Vulnerable NIST National Vulnerability Database
Oracle Banking Payments version 14.5 Vulnerable NIST National Vulnerability Database
Oracle Banking Trade Finance version 14.5 Vulnerable NIST National Vulnerability Database
Oracle Banking Treasury Management version 14.5 Vulnerable NIST National Vulnerability Database
Oracle Business Process Management Suite version 12.2.1.4.0version 12.2.1.3.0 Vulnerable NIST National Vulnerability Database
Oracle Commerce Guided Search version 11.3.2 Vulnerable NIST National Vulnerability Database
Oracle Communications Billing And Revenue Management version 12.0.0.4 Vulnerable NIST National Vulnerability Database
Oracle Communications Cloud Native Core Service Communication Proxy version 1.14.0 Vulnerable NIST National Vulnerability Database
Oracle Communications Cloud Native Core Unified Data Repository version 1.14.0 Vulnerable NIST National Vulnerability Database
Oracle Communications Diameter Intelligence Hub ≥ 8.0.0 and ≤ 8.2.3 Vulnerable NIST National Vulnerability Database
Oracle Communications Messaging Server version 8.1 Vulnerable NIST National Vulnerability Database
Oracle Communications Session Route Manager ≥ 8.0.0 and ≤ 8.2.5 Vulnerable NIST National Vulnerability Database
Oracle Financial Services Crime And Compliance Management Studio version 8.0.8.3.0version 8.0.8.2.0 Vulnerable NIST National Vulnerability Database
Oracle Financial Services Enterprise Case Management version 8.0.7.2.0version 8.0.8.1.0 Vulnerable NIST National Vulnerability Database
Oracle Flexcube Universal Banking version 14.5version 12.4≥ 14.0.0 and ≤ 14.3.0 Vulnerable NIST National Vulnerability Database
Oracle Healthcare Data Repository version 8.1.0 Vulnerable NIST National Vulnerability Database
Oracle Insurance Policy Administration version 11.3.0version 11.0.2version 11.1.0version 11.2.8version 11.3.1 Vulnerable NIST National Vulnerability Database
Oracle Peoplesoft Enterprise Peopletools version 8.59version 8.58version 8.57 Vulnerable NIST National Vulnerability Database
Oracle Primavera Unifier version 20.12version 19.12version 18.8≥ 17.7 and ≤ 17.12 Vulnerable NIST National Vulnerability Database
Oracle Utilities Testing Accelerator version 6.0.0.1.1version 6.0.0.2.2version 6.0.0.3.1 Vulnerable NIST National Vulnerability Database
Oracle WebCenter Portal version 12.2.1.4.0version 12.2.1.3.0 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
7.5 CVSS 3.1 High 3.9 3.6 nvd@nist.gov via NIST National Vulnerability Database
5.0 CVSS 2.0 Medium 10.0 2.9 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-770 · Allocation of Resources Without Limits or Throttling

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 10.61%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Track CPU/memory spikes and availability drops correlated with request patterns.
web/proxy/WAF logsnetwork IDS/IPSresource metrics

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · apache software foundation/apache commons compress
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 7.5
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • 2021
  • CVE published
    Jul 13, 2021 · apache

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

22 on the record

Elsewhere on this site

Apache Software Foundation
every CVE for this vendor
Denial of service
same class
CWE-770
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-87264 Improper Access Control in Oracle Peoplesoft Enterprise Peopletools Sep 15, 2026
  • CVE-2026-83065 Improper Access Control in Oracle WebCenter Portal Sep 15, 2026
  • CVE-2026-83064 Improper Access Control in Oracle WebCenter Portal Sep 15, 2026
  • CVE-2026-83049 Improper Access Control in Oracle WebCenter Portal Sep 15, 2026
  • CVE-2026-83051 Improper Access Control in Oracle WebCenter Portal Sep 15, 2026
  • CVE-2026-83048 Improper Access Control in Oracle WebCenter Portal Sep 15, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2021-35517 is "Apache Commons Compress 1.1 to 1.20 denial of service vulnerability", rated High. It affects Commons Compress (Apache Software Foundation); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 10.61% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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