curl and libcurl before 7.50.2, when built with NSS and the libnsspem.so library is available at runtime, allow remote attackers to hijack t
curl and libcurl before 7.50.2, when built with NSS and the libnsspem.so library is available at runtime, allow remote attackers to hijack the authentication of a TLS connection by leveraging reuse of a previously loaded client certificate from file for a connection for which no certificate has been set, a different vulnerability than CVE-2016-5420.
- Published
- Oct 3, 2016
- Updated
- Jun 16, 2026
- EPSS
- 8.2% · 95th percentile
- CWE
- CWE-287
Sign in to follow · You’ll be notified if a followed record enters KEV, gets an exploit or is updated.
Report tools
Action score
32
Monitor
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 2 / 30 · 8.2%
Affected systems
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- haxx libcurlup to 7.50.1 inclusive
- opensuse leap42.1
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 | before 7.50.2-r0 | 7.50.2-r0 |
| Alpine:v3.11 | curl | before 7.50.2 | 7.50.2 |
| Alpine:v3.2 | curl | before 7.49.1-r2 | 7.49.1-r2 |
| Alpine:v3.9 | curl | before 7.50.2-r1 | 7.50.2-r1 |
| Debian:12 | curl | before 7.51.0-1 | 7.51.0-1 |
| Debian:7 | curl | before 7.26.0-1+wheezy15 | 7.26.0-1+wheezy15 |
| Debian:8 | curl | before 7.38.0-4+deb8u13 | 7.38.0-4+deb8u13 |
| Red Hat:enterprise_linux:7::client | curl | before 0:7.29.0-35.el7 | 0:7.29.0-35.el7 |
| Red Hat:enterprise_linux:7::client | curl-debuginfo | before 0:7.29.0-35.el7 | 0:7.29.0-35.el7 |
| Red Hat:enterprise_linux:7::client | libcurl | before 0:7.29.0-35.el7 | 0:7.29.0-35.el7 |
| Red Hat:enterprise_linux:7::client | libcurl-devel | before 0:7.29.0-35.el7 | 0:7.29.0-35.el7 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-curl | before 0:7.61.1-1.el6 | 0:7.61.1-1.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-curl-debuginfo | before 0:7.61.1-1.el6 | 0:7.61.1-1.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-httpd | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-httpd-debuginfo | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-httpd-devel | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-httpd-manual | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-httpd-tools | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-libcurl | before 0:7.61.1-1.el6 | 0:7.61.1-1.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-libcurl-devel | before 0:7.61.1-1.el6 | 0:7.61.1-1.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-libnghttp2 | before 0:1.7.1-7.el6 | 0:1.7.1-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-libnghttp2-devel | before 0:1.7.1-7.el6 | 0:1.7.1-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-mod_ldap | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-mod_proxy_html | before 1:2.4.34-7.el6 | 1:2.4.34-7.el6 |
+28
Same product
opensuse: all recordsOther highest-scoring records for the same primary product.
- CVE-2016-0749The smartcard interaction in SPICE allows remote attackers to cause a denial of service (QEMU-KVM process crash) or possibly execute arbitra42Plan
- CVE-2015-8863Off-by-one error in the tokenadd function in jv_parse.c in jq allows remote attackers to cause a denial of service (crash) via a long JSON-e41Plan
- CVE-2019-18903wicked: Use-after-free when receiving invalid DHCP6 IA_PD option40Plan
- CVE-2019-18902wicked: Use-after-free when receiving invalid DHCP6 client options40Plan
- CVE-2016-4007Multiple unspecified vulnerabilities in the obs-service-extract_file package before 0.3-5.1 in openSUSE Leap 42.1 and before 0.3-3.1 in open40Plan
- CVE-2016-3982Off-by-one error in the bmp_rle4_fread function in pngxrbmp.c in OptiPNG before 0.7.6 allows remote attackers to cause a denial of service (36Monitor
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 | 7.50.2-r0 · Alpine:v3.10 | Package registry (OSV) |
| debian:curl | 7.51.0-1 · Debian:12 | Package registry (OSV) |
| red hat:curl | 0:7.29.0-35.el7 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:curl-debuginfo | 0:7.29.0-35.el7 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:httpd24-curl | 0:7.61.1-1.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-curl-debuginfo | 0:7.61.1-1.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-httpd | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-httpd-debuginfo | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-httpd-devel | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-httpd-manual | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-httpd-tools | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-libcurl | 0:7.61.1-1.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:libcurl | 0:7.29.0-35.el7 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| red hat:libcurl-devel | 0:7.29.0-35.el7 · Red Hat:enterprise_linux:7::client | Package registry (OSV) |
| suse:curl | 7.37.0-28.1 · SUSE:Linux Enterprise Desktop 12 SP1 | Package registry (OSV) |
| suse:curl-openssl1 | 7.19.7-1.61.1 · SUSE:Linux Enterprise Server 11-SECURITY | 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
- none
- Integrity
- high · 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
- High
- Availability impact
- None
Weakness class (CWE)
CWE-287 · Improper AuthenticationCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
nvd-primary
Root cause
Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.
The bug in code
The whole CWE-287 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
app.use("/admin", requireSession, adminRouter);
// Route added later skips the middlewareapp.post("/admin-api/config", updateConfig);Fixed
const admin = express.Router();admin.use(requireSession, requireRole("admin"));
admin.post("/config", updateConfig);app.use("/admin", admin);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)
- Authentication AbuseCAPEC-114Medium
- Authentication BypassCAPEC-115Medium
- Identity SpoofingCAPEC-151likelihood: Medium · Medium
- Fake the Source of DataCAPEC-194Medium
- Exploiting Trust in ClientCAPEC-22likelihood: High · High
- Utilizing REST's Trust in the System Resource to Obtain Sensitive DataCAPEC-57likelihood: Medium · Very High
- Session HijackingCAPEC-593likelihood: High · Very High
- Token ImpersonationCAPEC-633Medium
ATT&CK techniques
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; 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 helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- lists.opensuse.org/opensuse-updates/2016-09/msg00094.html
- rhn.redhat.com/errata/RHSA-2016-2575.html
- rhn.redhat.com/errata/RHSA-2016-2957.html
- www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
- www.securityfocus.com/bid/92754
- www.securitytracker.com/id/1036739
- access.redhat.com/errata/RHSA-2018:3558
- bugzilla.redhat.com/show_bug.cgi?id=1373229
- curl.haxx.se/docs/adv_20160907.html
- github.com/curl/curl/commit/curl-7_50_2~32
- lists.debian.org/debian-lts-announce/2018/11/msg00005.html
- security.gentoo.org/glsa/201701-47
Vendor advisories and official records. Exploit/PoC links are deliberately left out.