Curl versions 7.33.0 through 7.61.1 are vulnerable to a buffer overrun in the SASL authentication code that may lead to denial of service.
- Published
- Oct 31, 2018
- Updated
- Jun 16, 2026
- EPSS
- 5.8% · 93th percentile
- CWE
- CWE-122
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Report tools
Action score
41
Plan
Add it to your regular patch cycle.
- CVSS
- 39 / 40 · 9.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 2 / 30 · 5.8%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 9.8
- CNA · redhat
- 4.3
- 5.5 point gap
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| haxx | curl | cpe:2.3:a:haxx:curl |
| debian | debian linux | cpe:2.3:o:debian:debian_linux |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux14.04
- canonical ubuntu linux16.04
- canonical ubuntu linux18.04
- canonical ubuntu linux18.10
- debian debian linux8.0
- debian debian linux9.0
- haxx curl7.33.0 and later · up to 7.61.1 inclusive
Versions reported by the vendor
Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.
The Curl Project curl:
- from 7.33.0 to 7.61.1affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Alpine:v3.10 | curl | from 7.33.0 · before 7.62.0-r0 | 7.62.0-r0 |
| Alpine:v3.5 | curl | from 7.33.0 · before 7.61.1-r1 | 7.61.1-r1 |
| Debian:12 | curl | before 7.62.0-1 | 7.62.0-1 |
| Debian:8 | curl | before 7.38.0-4+deb8u13 | 7.38.0-4+deb8u13 |
| Debian:9 | curl | before 7.52.1-5+deb9u8 | 7.52.1-5+deb9u8 |
| SUSE:Linux Enterprise Desktop 12 SP4 | curl | before 7.60.0-4.3.1 | 7.60.0-4.3.1 |
| SUSE:Linux Enterprise Module for Basesystem 15 | curl | before 7.60.0-3.14.3 | 7.60.0-3.14.3 |
| SUSE:OpenStack Cloud 7 | curl | before 7.37.0-37.37.1 | 7.37.0-37.37.1 |
Same product
haxx: all recordsOther 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 t50Plan
- 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-leak45Plan
- CVE-2019-5482Heap buffer overflow in the TFTP protocol handler in cURL 7.19.4 to 7.65.3.44Plan
- CVE-2017-8817The FTP wildcard function in curl and libcurl before 7.57.0 allows remote attackers to cause a denial of service (out-of-bounds read and app42Plan
- CVE-2017-8816The NTLM authentication feature in curl and libcurl before 7.57.0 on 32-bit platforms allows attackers to cause a denial of service (integer42Plan
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 | 7.62.0-r0 · Alpine:v3.10 | Package registry (OSV) |
| debian:curl | 7.62.0-1 · Debian:12 | Package registry (OSV) |
| suse:curl | 7.60.0-3.14.3 · SUSE:Linux Enterprise Module for Basesystem 15 | 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.
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.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
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
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-122 · Heap-based Buffer OverflowCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvd-primary
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✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- usn.ubuntu.com/3805-1/
- www.securitytracker.com/id/1042012
- bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16839
- curl.haxx.se/docs/CVE-2018-16839.html
- github.com/curl/curl/commit/f3a24d7916b9173c69a3e0ee790102993833d6c5
- lists.apache.org/thread.html/8338a0f605bdbb3a6098bb76f666a95fc2b2f53f37fa1ecc89f1146f%40%3Cdevnull.infra.apache.org%3E
- lists.debian.org/debian-lts-announce/2018/11/msg00005.html
- security.gentoo.org/glsa/201903-03
- www.debian.org/security/2018/dsa-4331
Vendor advisories and official records. Exploit/PoC links are deliberately left out.