CVE-2004-1440: Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an…
Noroxi assessment
Priority: Monitor (action score 31/100)
- 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: 4.1% (FIRST EPSS); higher than 90.9% of all records.
- No special conditions are required; it is repeatable.
- Fixed version: putty (Debian:12) 0.56-1.
Low priority for now. Upgrade to putty (Debian:12) 0.56-1 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
Multiple heap-based buffer overflows in the modpow function in PuTTY before 0.55 allow (1) remote attackers to execute arbitrary code via an SSH2 packet with a base argument that is larger than the mod argument, which causes the modpow function to write memory before the beginning of its buffer, and (2) remote malicious servers to cause a denial of service (client crash) and possibly execute arbitrary code via a large bignum during authentication.
- Published
- Dec 31, 2004
- Updated
- Jun 16, 2026
- EPSS
- 4.1% · 90th percentile
- CWE
- —
Report tools
Action score
31
Low priority for now.
- CVSS
- 30 / 40 · 7.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 4.1%
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
If any of these changes, we'll tell you in the daily email digest.
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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.
We use this product, ask for helpAffected 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 |
|---|---|---|
| putty | putty | cpe:2.3:a:putty:putty |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- putty putty0.48
- putty putty0.49
- putty putty0.50
- putty putty0.51
- putty putty0.52
- putty putty0.53
- putty putty0.53b
- putty putty0.54
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | putty | before 0.56-1 | 0.56-1 |
Same product
putty: all recordsOther highest-scoring records for the same primary product.
- CVE-2017-6542The ssh_agent_channel_data function in PuTTY before 0.68 allows remote attackers to have unspecified impact via a large length value in an…46Plan
- CVE-2004-1008Integer signedness error in the ssh2_rdpkt function in PuTTY before 0.56 allows remote attackers to execute arbitrary code via a…42Plan
- CVE-2019-9898Potential recycling of random numbers used in cryptography exists within PuTTY before 0.71.40Plan
Published before and after this one in the same product
- ← EarlierCVE-2003-0048Feb 19, 2003 · PuTTY 0.53b and earlier does not clear logon credentials from memory, including plaintext passwords, which could allow attackers with…18Monitor
- ← EarlierCVE-2003-0069Mar 18, 2003 · The PuTTY terminal emulator 0.53 allows attackers to modify the window title via a certain character escape sequence and then insert it…31Monitor
- Later →CVE-2005-0467Feb 21, 2005 · Multiple integer overflows in the (1) sftp_pkt_getstring and (2) fxp_readdir_recv functions in the PSFTP and PSCP clients for PuTTY 0.56…31Monitor
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 |
|---|---|---|
| debian:putty | 0.56-1 · Debian:12 | 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.
Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.
Technical details
Attack conditions
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- P · data can be read
- Integrity
- P · data or configuration can be modified
- Availability
- P · the service can be disrupted
- Attack complexity
- Low
- Confidentiality impact
- P
- Integrity impact
- P
- Availability impact
- P
Weakness class (CWE)
—
CVSS vector
AV:N/AC:L/Au:N/C:P/I:P/A:P
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.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log (1)
- Fix✗ → ✓
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References
Show all references (6 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.