CVE-2003-0899

Exp

Buffer overflow in defang in libhttpd.c for thttpd 2.21 to 2.23b1 allows remote attackers to execute arbitrary code via requests that contain '<' or '>' characters, which trigger the overflow when the characters are expanded to "&lt;" and "&gt;" sequences.

Published: 2003-11-03 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2003-0899 is rated High Exploit Risk (89.5/100): CVSS Critical severity, with high exploitation likelihood (EPSS 21.68%, 97th percentile). 4 public exploit reference(s) are indexed (Exploit-DB). EPSS rose +1.22% over the last day, indicating growing attacker interest. Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2003-0899

EDB-ID Source Kind Published Link
23306 exploit_db edb 2003-10-27 Exploit-DB ↗
23305 exploit_db edb 2003-10-27 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2003-0899

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 20.46% 21.68% +1.22%
2 2025-12-28 36.22% 20.46% -15.76%
3 2025-12-27 — 36.22% —

Full EPSS history (18 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2003-0899

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2003-0899

OS Trackers for CVE-2003-0899

vendor priority summary link
ubuntu medium CVE-2003-0899 medium priority: Ubuntu including 1 source packages (thttpd), 4 status rows across 4 suites (dapper, edgy, feisty, upstream): released 3, needs-triage 1. https://ubuntu.com/security/CVE-2003-0899

NVD evaluator notes for CVE-2003-0899

Solution: This vulnerability is addressed in the following product release: Acme Labs, thttpd, 2.24

Affected software / configurations for CVE-2003-0899

Vendor Product Version Raw CPE
acme thttpd >= 2.21, < 2.23 cpe:2.3:a:acme:thttpd:*:*:*:*:*:*:*:*
acme thttpd 2.23 cpe:2.3:a:acme:thttpd:2.23:-:*:*:*:*:*:*
acme thttpd 2.23 cpe:2.3:a:acme:thttpd:2.23:b1:*:*:*:*:*:*

References for CVE-2003-0899

URL Tags
http://marc.info/?l=bugtraq&m=106729188224252&w=2 Exploit Mailing List
http://secunia.com/advisories/10092 Broken Link Patch Vendor Advisory
http://www.osvdb.org/2729 Broken Link
http://www.securityfocus.com/bid/8906 Broken Link Exploit Patch Third Party Advisory VDB Entry
http://www.texonet.com/advisories/TEXONET-20030908.txt Broken Link URL Repurposed
https://exchange.xforce.ibmcloud.com/vulnerabilities/13530 Third Party Advisory VDB Entry
https://www.debian.org/security/2003/dsa-396 Broken Link
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