When doing a TFTP transfer and curl/libcurl is given a URL that contains a very long file name (longer than about 515 bytes), the file name
When doing a TFTP transfer and curl/libcurl is given a URL that contains a very long file name (longer than about 515 bytes), the file name is truncated to fit within the buffer boundaries, but the buffer size is still wrongly updated to use the untruncated length. This too large value is then used in the sendto() call, making curl attempt to send more data than what is actually put into the buffer. The endto() function will then read beyond the end of the heap based buffer. A malicious HTTP(S) server could redirect a vulnerable libcurl-using client to a crafted TFTP URL (if the client hasn't restricted which protocols it allows redirects to) and trick it to send private memory contents to a remote server over UDP. Limit curl's redirect protocols with --proto-redir and libcurl's with CURLOPT_REDIR_PROTOCOLS.
- Published
- Oct 4, 2017
- Updated
- Jun 16, 2026
- EPSS
- 4.0% · 90th percentile
- CWE
- CWE-200
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Report tools
Action score
27
Monitor
Low priority for now.
- CVSS
- 26 / 40 · 6.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.0%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| haxx | libcurl | cpe:2.3:a:haxx:libcurl |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- haxx libcurl7.15.0
- haxx libcurl7.15.1
- haxx libcurl7.15.2
- haxx libcurl7.15.3
- haxx libcurl7.15.4
- haxx libcurl7.15.5
- haxx libcurl7.16.0
- haxx libcurl7.16.1
- haxx libcurl7.16.2
- haxx libcurl7.16.3
- haxx libcurl7.16.4
- haxx libcurl7.17.0
- haxx libcurl7.17.1
- haxx libcurl7.18.0
- haxx libcurl7.18.1
- haxx libcurl7.18.2
- haxx libcurl7.19.0
- haxx libcurl7.19.1
- haxx libcurl7.19.2
- haxx libcurl7.19.3
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 7.55.0-r0 | 7.55.0-r0 |
| Debian:12 | curl | before 7.55.0-1 | 7.55.0-1 |
| Debian:7 | curl | before 7.26.0-1+wheezy20 | 7.26.0-1+wheezy20 |
| Debian:8 | curl | before 7.38.0-4+deb8u6 | 7.38.0-4+deb8u6 |
| Debian:9 | curl | before 7.52.1-5+deb9u1 | 7.52.1-5+deb9u1 |
| openSUSE:Tumbleweed | curl | before 7.79.1-1.1 | 7.79.1-1.1 |
| 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 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-mod_session | before 0:2.4.34-7.el6 | 0:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-mod_ssl | before 1:2.4.34-7.el6 | 1:2.4.34-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-nghttp2 | before 0:1.7.1-7.el6 | 0:1.7.1-7.el6 |
| Red Hat:rhel_software_collections:3::el6 | httpd24-nghttp2-debuginfo | before 0:1.7.1-7.el6 | 0:1.7.1-7.el6 |
| Red Hat:rhel_software_collections:3::el7 | httpd24-curl | before 0:7.61.1-1.el7 | 0:7.61.1-1.el7 |
+21
Same product
haxx: all recordsOther highest-scoring records for the same primary product.
- CVE-2023-38545This flaw makes curl overflow a heap based buffer in the SOCKS5 proxy
handshake.63This week
- CVE-2019-5436A heap buffer overflow in the TFTP receiving code allows for DoS or arbitrary code execution in libcurl versions 7.19.4 through 7.64.1.46Plan
- CVE-2019-3822libcurl versions from 7.36.0 to before 7.64.0 are vulnerable to a stack-based buffer overflow.43Plan
- CVE-2018-14618curl before version 7.61.1 is vulnerable to a buffer overrun in the NTLM authentication code.42Plan
- CVE-2016-8622The URL percent-encoding decode function in libcurl before 7.51.0 is called `curl_easy_unescape`.40Plan
- CVE-2021-22945When sending data to an MQTT server, libcurl <= 7.73.0 and 7.78.0 could in some circumstances erroneously keep a pointer to an already freed38Monitor
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 | 7.55.0-r0 · Alpine:v3.10 | Package registry (OSV) |
| debian:curl | 7.55.0-1 · Debian:12 | Package registry (OSV) |
| opensuse:curl | 7.79.1-1.1 · openSUSE:Tumbleweed | 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:httpd24-libcurl-devel | 0:7.61.1-1.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-libnghttp2 | 0:1.7.1-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-libnghttp2-devel | 0:1.7.1-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| red hat:httpd24-mod_ldap | 0:2.4.34-7.el6 · Red Hat:rhel_software_collections:3::el6 | Package registry (OSV) |
| suse:curl | 7.37.0-37.3.1 · SUSE:Linux Enterprise Desktop 12 SP2 | Package registry (OSV) |
| suse:curl-openssl1 | 7.19.7-1.70.3.1 · 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.
No commit or PR link among the references.
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.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- none
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- None
- Availability impact
- None
Weakness class (CWE)
CWE-200 · Exposure of Sensitive Information to an Unauthorized ActorCVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
nvd-secondary
Root cause
The extension requests broader permissions than its function needs and sends the data it collects out for purposes beyond its stated function.
The bug in code
The whole CWE-200 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
{ "permissions": ["tabs", "<all_urls>"], "background": { "service_worker": "analytics.js" }}Fixed
{ "permissions": ["activeTab"], "host_permissions": ["https://yildiz.example/*"]}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)
- ExcavationCAPEC-116likelihood: High · Medium
- Subverting Environment Variable ValuesCAPEC-13likelihood: High · Very High
- FootprintingCAPEC-169likelihood: High · Very Low
- Exploiting Trust in ClientCAPEC-22likelihood: High · High
- FingerprintingCAPEC-224likelihood: High · Very Low
- ICMP Echo Request PingCAPEC-285likelihood: Medium · Low
- TCP SYN ScanCAPEC-287Low
- Enumerate Mail Exchange (MX) RecordsCAPEC-290Low
ATT&CK techniques
- System Service DiscoveryT1007
- System Network Configuration DiscoveryT1016
- Remote System DiscoveryT1018
- System Owner/User DiscoveryT1033
- Masquerading: Match Legitimate Name or LocationT1036.005
- Network Service ScanningT1046
- System Network Connections DiscoveryT1049
- Process DiscoveryT1057
- Permission Groups DiscoveryT1069
- System Information DiscoveryT1082
- File and Directory DiscoveryT1083
- Account DiscoveryT1087
- Multi-Factor Authentication InterceptionT1111
- Peripheral Device DiscoveryT1120
- System Time DiscoveryT1124
- Access Token Manipulation:Token Impersonation/TheftT1134.001
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
- www.debian.org/security/2017/dsa-3992
- www.securityfocus.com/bid/100286
- www.securitytracker.com/id/1039118
- access.redhat.com/errata/RHSA-2018:3558
- curl.haxx.se/docs/adv_20170809B.html
- security.gentoo.org/glsa/201709-14
- support.apple.com/HT208221
Vendor advisories and official records. Exploit/PoC links are deliberately left out.