cbcvebase.
CVE-2023-38039
published 2023-09-15

CVE-2023-38039: When curl retrieves an HTTP response, it stores the incoming headers so that they can be accessed later via the libcurl headers API. However, curl did not have…

PriorityP359high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
63.79%
99.1th percentile
When curl retrieves an HTTP response, it stores the incoming headers so that they can be accessed later via the libcurl headers API. However, curl did not have a limit in how many or how large headers it would accept in a response, allowing a malicious server to stream an endless series of headers and eventually cause curl to run out of heap memory.

Affected

49 ranges· showing 25
VendorProductVersion rangeFixed in
applemacos_monterey
applemacos_sonoma
applemacos_ventura
curlcurl>= 8.3.0 < 8.3.08.3.0
debiancurl< curl 7.88.1-10+deb12u3 (bookworm)curl 7.88.1-10+deb12u3 (bookworm)
fedoraprojectfedora
fedoraprojectfedora
fedoraprojectfedora
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 8.3.0-r08.3.0-r0
haxxcurl>= 0 < 7.88.1-10+deb12u37.88.1-10+deb12u3
haxxcurl>= 0 < 8.3.0-18.3.0-1
haxxcurl>= 0 < 8.3.0-18.3.0-1
haxxcurl>= 7.84.0 < 8.3.08.3.0
microsoftwindows_10_1809< 10.0.17763.512210.0.17763.5122
microsoftwindows_10_21h2< 10.0.19044.369310.0.19044.3693
microsoftwindows_10_22h2< 10.0.19045.369310.0.19045.3693
microsoftwindows_11_21h2< 10.0.22000.260010.0.22000.2600

Detection & IOCsextracted from sources · hover to see the quote

  • A malicious server streams an endless series of HTTP response headers to exhaust curl client heap memory; monitor for abnormally large or unbounded HTTP response header counts from a server to a curl client
  • Versions of curl.exe prior to 8.4.0 on Windows are vulnerable; use WDAC policy to deny execution of \system32\curl.exe with MaximumFileVersion set to 8.4.0.0 as a detection/blocking boundary
  • Vulnerable path on Windows is \system32\curl.exe; flag execution of this binary at versions below 8.4.0 as potentially exploitable
  • Exploit requires attacker-controlled server; an attacker must convince the victim to connect curl to a compromised server — monitor for curl connections to untrusted or anomalous HTTP endpoints resulting in process memory exhaustion or crash
  • ·curl version 8.4.0 is the fixed version; any curl deployment below this version is vulnerable to the unbounded header memory exhaustion
  • ·Red Hat Enterprise Linux 6, 7, 8, and 9 ship a curl package that is NOT affected by this CVE
  • ·The vulnerability is exploitable only over HTTP protocol and requires a network-reachable attacker-controlled server; it is not remotely exploitable without victim interaction

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
osv7.5HIGH
vendor_debian7.5HIGH
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
vendor_oracle6.5HIGH
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