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CVE-2023-38545

Haxx Libcurl buffer overflow

9.8 CRITICALEPSS 78.7%
  1. Published18 Oct 2023

Description

This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy handshake. When curl is asked to pass along the host name to the SOCKS5 proxy to allow that to resolve the address instead of it getting done by curl itself, the maximum length that host name can be is 255 bytes. If the host name is detected to be longer, curl switches to local name resolving and instead passes on the resolved address only. Due to this bug, the local variable that means "let the host resolve the name" could get the wrong value during a slow SOCKS5 handshake, and contrary to the intention, copy the too long host name to the target buffer instead of copying just the resolved address there. The target buffer being a heap based buffer, and the host name coming from the URL that curl has been told to operate with.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

Haxx Libcurl≥ 7.69.0 < 8.4.0
Netapp Active Iq Unified Managerall versions
Netapp Oncommand Insightall versions
Netapp Oncommand Workflow Automationall versions
Fedoraproject Fedora37
Microsoft Windows 10 1809< 10.0.17763.5122
Microsoft Windows 10 21h2< 10.0.19044.3693
Microsoft Windows 10 22h2< 10.0.19045.3693
Microsoft Windows 11 21h2< 10.0.22000.2600
Microsoft Windows 11 22h2< 10.0.22621.2715
Microsoft Windows 11 23h2< 10.0.22631.2715
Microsoft Windows Server 2019< 10.0.17763.5122
Microsoft Windows Server 2022< 10.0.20348.2113

Remediation

Fixed in
Haxx Libcurl≥ 8.4.0
Microsoft Windows 10 1809≥ 10.0.17763.5122
Microsoft Windows 10 21h2≥ 10.0.19044.3693
Microsoft Windows 10 22h2≥ 10.0.19045.3693
Microsoft Windows 11 21h2≥ 10.0.22000.2600
Microsoft Windows 11 22h2≥ 10.0.22621.2715
Microsoft Windows 11 23h2≥ 10.0.22631.2715
Microsoft Windows Server 2019≥ 10.0.17763.5122
Microsoft Windows Server 2022≥ 10.0.20348.2113

References

and 11 more references

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Frequently asked

Is CVE-2023-38545 being actively exploited?

CVE-2023-38545 is not in the CISA KEV catalog. Its EPSS exploit probability is 78.7%.

How severe is CVE-2023-38545?

CVE-2023-38545 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 78.7% probability of exploitation.

Which products are affected by CVE-2023-38545?

Affected products include Haxx Libcurl, Netapp Active Iq Unified Manager, Netapp Oncommand Insight, Netapp Oncommand Workflow Automation, Fedoraproject Fedora, and 8 more.

How do I fix CVE-2023-38545?

Upgrade affected software to a fixed version, for example Haxx Libcurl 8.4.0, Microsoft Windows 10 1809 10.0.17763.5122, Microsoft Windows 10 21h2 10.0.19044.3693 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2023-38545 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.