cbcvebase.
CVE-2021-22947
published 2021-09-29

CVE-2021-22947: 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…

PriorityP335medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
2.80%
84.9th percentile
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.

Affected

51 ranges· showing 25
VendorProductVersion rangeFixed in
applemacos< 12.312.3
applemacos_monterey
debiancurl< curl 7.79.1-1 (bookworm)curl 7.79.1-1 (bookworm)
debiandebian_linux
debiandebian_linux
debiandebian_linux
fedoraprojectfedora
fedoraprojectfedora
haxxcurl>= 0 < 7.74.0-1.3+deb11u27.74.0-1.3+deb11u2
haxxcurl>= 0 < 7.79.1-17.79.1-1
haxxcurl>= 0 < 7.79.1-17.79.1-1
haxxcurl>= 0 < 7.79.1-17.79.1-1
haxxcurl>= 0 < 7.58.0-2ubuntu3.167.58.0-2ubuntu3.16
haxxcurl>= 0 < 7.58.0-2ubuntu3.157.58.0-2ubuntu3.15
haxxcurl>= 0 < 7.68.0-1ubuntu2.77.68.0-1ubuntu2.7
haxxcurl>= 0 < 7.35.0-1ubuntu2.20+esm87.35.0-1ubuntu2.20+esm8
haxxcurl>= 0 < 7.35.0-1ubuntu2.20+esm97.35.0-1ubuntu2.20+esm9
haxxcurl>= 0 < 7.47.0-1ubuntu2.19+esm17.47.0-1ubuntu2.19+esm1
haxxcurl>= 0 < 7.47.0-1ubuntu2.19+esm27.47.0-1ubuntu2.19+esm2
haxxcurl>= 7.20.0 < 7.79.07.79.0
httpsgithub.com_curl_curl
msrcwindows_10_version_1809
msrcwindows_10_version_1909
msrcwindows_10_version_20h2
msrcwindows_10_version_21h1

CVSS provenance

nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
osv9.1CRITICAL
vendor_ubuntu9.1CRITICAL
vendor_debian5.9MEDIUM
vendor_msrc5.9CRITICAL
vendor_redhat5.9MEDIUM
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