curl 7.61.0 through 7.76.1 suffers from exposure of data element to wrong session due to a mistake in the code for CURLOPT_SSL_CIPHER_LIST when libcurl is built to use the Schannel TLS library. The selected cipher set was stored in a single "static" variable in the library, which has the surprising side-effect that if an application sets up multiple concurrent transfers, the last one that sets the ciphers will accidentally control the set used by all transfers. In a worst-case scenario, this weakens transport security significantly.
CVE-2021-22897
Score 5.3 from GitHub Security Advisory published 2022-05-24. NVD baseline CVSS 5.3; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.3
- EG Score
- 5.3(medium)
- EPSS
- 85.7%
- KEV
- Not listed
Published
June 11, 2021
Last Modified
May 28, 2026
References (17)
- support@hackeronehttps://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- support@hackeronehttps://curl.se/docs/CVE-2021-22897.html
- support@hackeronehttps://github.com/curl/curl/commit/bbb71507b7bab52002f9b1e0880bed6a32834511
- support@hackeronehttps://hackerone.com/reports/1172857
- support@hackeronehttps://security.netapp.com/advisory/ntap-20210727-0007/
- support@hackeronehttps://www.oracle.com//security-alerts/cpujul2021.html
- support@hackeronehttps://www.oracle.com/security-alerts/cpuapr2022.html
- support@hackeronehttps://www.oracle.com/security-alerts/cpujan2022.html
- af854a3a-2127-422b-91ae-364da2661108https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- af854a3a-2127-422b-91ae-364da2661108https://curl.se/docs/CVE-2021-22897.html
- af854a3a-2127-422b-91ae-364da2661108https://github.com/curl/curl/commit/bbb71507b7bab52002f9b1e0880bed6a32834511
- af854a3a-2127-422b-91ae-364da2661108https://hackerone.com/reports/1172857
- af854a3a-2127-422b-91ae-364da2661108https://security.netapp.com/advisory/ntap-20210727-0007/
- af854a3a-2127-422b-91ae-364da2661108https://www.oracle.com//security-alerts/cpujul2021.html
- af854a3a-2127-422b-91ae-364da2661108https://www.oracle.com/security-alerts/cpuapr2022.html
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
All Vendor Advisories
(1)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
Data Freshness Timeline
(refreshed 9× in last 7d / 43× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-11 08:25 UTCEPSS rescore
- 2026-07-09 19:07 UTCEPSS rescore
- 2026-07-08 15:12 UTCEPSS rescore
- 2026-07-07 13:43 UTCEPSS rescore
- 2026-07-06 16:25 UTCEPSS rescore
- 2026-07-06 02:21 UTCEPSS rescore
- 2026-07-06 02:21 UTCEPSS rescore
- 2026-07-05 02:28 UTCEPSS rescore
- 2026-07-05 02:28 UTCEPSS rescore
- 2026-07-04 06:29 UTCEPSS rescore
- 2026-07-04 06:29 UTCEPSS rescore
- 2026-07-02 16:57 UTCEPSS rescore
- 2026-07-01 15:03 UTCEPSS rescore
- 2026-07-01 01:48 UTCOSV refresh
- 2026-06-30 23:20 UTCEPSS rescore
- 2026-06-30 23:20 UTCEPSS rescore
- 2026-06-28 14:05 UTCEPSS rescore
- 2026-06-28 04:54 UTCEPSS rescore
- 2026-06-28 04:54 UTCEPSS rescore
- 2026-06-27 03:06 UTCEPSS rescore
- 2026-06-27 03:06 UTCEPSS rescore
- 2026-06-25 13:48 UTCEPSS rescore
- 2026-06-25 13:48 UTCEPSS rescore
- 2026-06-24 14:03 UTCEPSS rescore
- 2026-06-24 14:03 UTCEPSS rescore
Show 55 moreShow fewer
- 2026-06-23 21:31 UTCEPSS rescore
- 2026-06-23 21:31 UTCEPSS rescore
- 2026-06-22 14:24 UTCEPSS rescore
- 2026-06-22 14:23 UTCEPSS rescore
- 2026-06-21 01:58 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-19 19:24 UTCEPSS rescore
- 2026-06-19 19:24 UTCEPSS rescore
- 2026-06-18 17:51 UTCEPSS rescore
- 2026-06-18 17:51 UTCEPSS rescore
- 2026-06-17 17:51 UTCEPSS rescore
- 2026-06-16 17:50 UTCEPSS rescore
- 2026-06-15 17:46 UTCEPSS rescore
- 2026-06-14 23:15 UTCEPSS rescore
- 2026-06-13 22:58 UTCEPSS rescore
- 2026-06-13 03:43 UTCOSV refresh
- 2026-06-12 23:10 UTCEPSS rescore
- 2026-06-12 23:10 UTCEPSS rescore
- 2026-06-11 13:58 UTCEPSS rescore
- 2026-06-10 22:16 UTCEPSS rescore
- 2026-06-10 22:16 UTCEPSS rescore
- 2026-06-10 13:20 UTCEPSS rescore
- 2026-06-08 14:15 UTCEPSS rescore
- 2026-06-08 14:15 UTCEPSS rescore
- 2026-06-07 15:23 UTCEPSS rescore
- 2026-06-07 15:23 UTCEPSS rescore
- 2026-06-06 13:46 UTCEPSS rescore
- 2026-06-06 13:46 UTCEPSS rescore
- 2026-06-06 13:46 UTCEPSS rescore
- 2026-06-05 22:45 UTCEPSS rescore
- 2026-06-05 22:45 UTCEPSS rescore
- 2026-06-05 06:09 UTCEPSS rescore
- 2026-06-05 06:09 UTCEPSS rescore
- 2026-06-05 06:08 UTCEPSS rescore
- 2026-06-04 13:10 UTCEPSS rescore
- 2026-06-02 20:11 UTCEPSS rescore
- 2026-06-02 20:11 UTCEPSS rescore
- 2026-06-01 13:50 UTCEPSS rescore
- 2026-06-01 13:50 UTCEPSS rescore
- 2026-05-31 22:29 UTCEPSS rescore
- 2026-05-31 22:29 UTCEPSS rescore
- 2026-05-31 00:15 UTCEPSS rescore
- 2026-05-31 00:15 UTCEPSS rescore
- 2026-05-29 13:42 UTCEPSS rescore
- 2026-05-28 13:43 UTCEPSS rescore
- 2026-05-28 13:43 UTCEPSS rescore
- 2026-05-27 13:39 UTCEPSS rescore
- 2026-05-26 15:00 UTCEG score recompute
- 2026-05-26 15:00 UTCVendor advisory
- 2026-05-26 15:00 UTCGHSA enrichment
- 2026-05-26 13:42 UTCEPSS rescore
- 2026-05-26 13:42 UTCEPSS rescore
- 2026-05-26 07:17 UTCEPSS rescore
- 2026-05-26 07:17 UTCEPSS rescore
- 2026-05-24 16:49 UTCEPSS rescore
Frequently asked(5)
What is CVE-2021-22897?
When was CVE-2021-22897 disclosed?
Is CVE-2021-22897 actively exploited?
What is the CVSS score of CVE-2021-22897?
How do I remediate CVE-2021-22897?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2021-22897
Is Your Infrastructure Affected by CVE-2021-22897?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.