Is CVE-2021-22947 being actively exploited?

It is not currently in CISA's KEV catalog. Its EPSS exploitation probability is 3%.

What products does CVE-2021-22947 affect?

Tracked products affected include curl, PeopleSoft Enterprise PeopleTools. Check the version you run to see whether it is affected.

How do I fix CVE-2021-22947?

Apply the vendor fix in your normal patch cycle. An official patch or advisory is available. Upgrade affected products to a fixed version.

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CVE-2021-22947

Q: What is CVE-2021-22947?

CVE-2021-22947 is a medium-severity software vulnerability (CWE-310) with a CVSS score of 5.9. When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that curl caches. curl would then upgrade to TL

MEDIUM severity · CVSS 5.9 · CWE-310

5.9CVSS MEDIUM

Summary

When curl >= 7.20.0 and <= 7.78.0 connects to an IMAP or POP3 server to retrieve data using STARTTLS to upgrade to TLS security, the server can respond and send back multiple responses at once that curl caches. curl would then upgrade to TLS but not flush the in-queue of cached responses but instead continue using and trustingthe responses it got *before* the TLS handshake as if they were authenticated.Using this flaw, it allows a Man-In-The-Middle attacker to first inject the fake responses, then pass-through the TLS traffic from the legitimate server and trick curl into sending data back to the user thinking the attacker's injected data comes from the TLS-protected server.

Impact & exploitability

Attack vectorNetwork

Attack complexityHigh

Privileges requiredNone

User interactionNone

Confidentiality impactNone

Integrity impactHigh

Availability impactNone

Exploit probability (EPSS)3%

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected products we track (2)

curl PeopleSoft Enterprise PeopleTools

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf ↗

CVE-2021-22947

Summary

Impact & exploitability

Affected products we track (2)

Recommendation

Additional information