CVE-2024-0853· NVD / CVE Program· CNA curl

OCSP verification bypass with TLS session reuse

Noroxi assessment

Priority: Monitor (action score 21/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 1.1% (FIRST EPSS); higher than 65.4% of all records.
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
Fixed version: curl (Alpine:v3.17) 8.6.0-r0; curl (Debian:13) 8.6.0-1; curl (openSUSE:Tumbleweed) 8.6.0-1.1.

Low priority for now. Upgrade to curl (Alpine:v3.17) 8.6.0-r0; curl (Debian:13) 8.6.0-1; curl (openSUSE:Tumbleweed) 8.6.0-1.1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

curl inadvertently kept the SSL session ID for connections in its cache even when the verify status (*OCSP stapling*) test failed. A subsequent transfer to the same hostname could then succeed if the session ID cache was still fresh, which then skipped the verify status check.

MediumCVSS 5.3 · v3.1—No exploit Fix available

Published: Feb 3, 2024
Updated: Jun 17, 2026
EPSS: 1.1% · 65th percentile
CWE: CWE-295

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 21 / 40 · 5.3 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 1.1%

CISA SSVC decision

Exploitation: proof of concept
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
haxx	curl	cpe:2.3:a:haxx:curl

Check your site's encryption

This vulnerability is about certificate validation or weak cryptography. The free SSL checker tests your certificate, enabled TLS versions and weak ciphers.

Run the SSL check

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

haxx curl8.5.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (curl). Independent of NVD's CPE analysis and usually ahead of it.

curl curl
- 8.5.0 and later · up to and including 8.5.0affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Alpine:v3.17	curl	before 8.6.0-r0	8.6.0-r0
Debian:13	curl	before 8.6.0-1	8.6.0-1
openSUSE:Tumbleweed	curl	before 8.6.0-1.1	8.6.0-1.1

Same product

haxx: all records

Other highest-scoring records for the same primary product.

CVE-2021-22901curl 7.75.0 through 7.76.1 suffers from a use-after-free vulnerability resulting in already freed memory being used when a TLS 1.3 session t
51Plan
CVE-2023-38039When curl retrieves an HTTP response, it stores the incoming headers so that they can be accessed later via the libcurl headers API.
47Plan
CVE-2024-2398HTTP/2 push headers memory-leak
45Plan

Published before and after this one in the same product

← EarlierCVE-2023-46218Dec 6, 2023 · This flaw allows a malicious HTTP server to set "super cookies" in curl that are then passed back to more origins than what is otherwise all
27Monitor
← EarlierCVE-2023-46219Dec 11, 2023 · When saving HSTS data to an excessively long file name, curl could end up removing all contents, making subsequent requests using that file
21Monitor
Later →CVE-2024-2004Mar 27, 2024 · Usage of disabled protocol
15Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
alpine:curl	8.6.0-r0 · Alpine:v3.17	Package registry (OSV)
debian:curl	8.6.0-1 · Debian:13	Package registry (OSV)
opensuse:curl	8.6.0-1.1 · openSUSE:Tumbleweed	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

Hiroki Kurosawafinder
Daniel Stenbergremediation developer

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

CVE-2024-237953 days apartQUIC certificate check bypass with wolfSSL
26Monitor
CVE-2024-8096221 days apartOCSP stapling bypass with GnuTLS
26Monitor
CVE-2025-4947480 days apartQUIC certificate check skip with wolfSSL
26Monitor
CVE-2023-28321253 days apartAn improper certificate validation vulnerability exists in curl <v8.1.0 in the way it supports matching of wildcard patterns when listed as
24Monitor
CVE-2025-5025480 days apartNo QUIC certificate pinning with wolfSSL
19Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: low · data or configuration can be modified
Availability: none

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: None
Integrity impact: Low
Availability impact: None

Weakness class (CWE)

CWE-295 · Improper Certificate Validation

CVSS vector

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

nvd-primary

Root cause

A certificate validation error is silently swallowed instead of terminating the connection. Often, code added for a test environment makes its way into production.

The bug in code

The whole CWE-295 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

kotlin

1override fun checkServerTrusted(chain: Array<X509Certificate>, type: String) {
2  // Left empty for the test environment
3}

Fixed

kotlin

1val client = OkHttpClient.Builder()
2  .certificatePinner(
3    CertificatePinner.Builder()
4      .add("api.sirius.example", "sha256/…")
5      .build()
6  ).build()

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:45 PM UTC

For records you follow, these changes also arrive as notifications. →

References

security.netapp.com/advisory/ntap-20240503-0012/

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records