CVE-2021-23047

mediumpriority · track · 21EPSS 0.006 · 48 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.60% (48th) EPSS

CVSS 5 · medium

Is it mine?

13 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

On version 16.x before 16.1.0, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.3, and all versions of 13.1.x, 12.1.x and 11.6.x, when BIG-IP APM performs Online Certificate Status Protocol (OCSP) verification of a certificate that contains Authority Information Access (AIA), undisclosed requests may cause an increase in memory use. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

cvss

Technical severity, 0–10. One row per scoring source.

5.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lprimary · NVD / NIST USexploitability 3.9 · impact 1.4

v3.15.3mediumAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lsecondary · FSTEC (BDU) RU

v3.14.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US

affected products (13)

Products and version ranges known to be affected.

n/a BIG-IP APM≤ 16.x before 16.1.0, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.3, and all versions of 13.1.x, 12.1.x and 11.6.xenisa_euvdEU
F5 Networks, Inc. BIG-IP Access Policy Manager11.6.1 → 11.6.5fstec_bduRU
F5 Networks, Inc. BIG-IP Access Policy Manager12.1.0 → 12.1.6fstec_bduRU
F5 Networks, Inc. BIG-IP Access Policy Manager13.1.0 → 13.1.4fstec_bduRU
F5 Networks, Inc. BIG-IP Access Policy Manager14.1.0 → 14.1.4.3fstec_bduRU
F5 Networks, Inc. BIG-IP Access Policy Manager15.1.0 → 15.1.3.1fstec_bduRU
F5 Networks, Inc. BIG-IP Access Policy Manager16.0.0 → 16.0.1fstec_bduRU
f5 big-ip access policy manager11.6.1 → 11.6.5nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip access policy manager12.1.0 → 12.1.6nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip access policy manager13.1.0 → 13.1.4nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip access policy manager14.1.0 → 14.1.4.3nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip access policy manager15.1.0 → 15.1.3.1nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip access policy manager16.0.0 → 16.0.1nvdUScpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-09-14modified 2026-06-17

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references (6)

External citations — patches, advisories, analysis.

scry

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