Celestialsoftware AbsoluteTelnet 11.24 out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Celestialsoftware AbsoluteTelnet 11.24. This affects an unknown part. Executing a manipulation can lead to out-of-bounds write. This vulnerability is tracked as CVE-2021-47764. The attack is restricted to local execution. Moreover, an exploit is present.

Detailsinfo

A vulnerability was found in Celestialsoftware AbsoluteTelnet 11.24. It has been declared as critical. This vulnerability affects an unknown code block. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

AbsoluteTelnet 11.24 contains a denial of service vulnerability that allows local attackers to crash the application by manipulating DialUp connection and license name fields. Attackers can generate a 1000-character payload and paste it into specific input fields to trigger application crashes and force unexpected termination.

The weakness was disclosed by Yehia Elghaly as 50511. The advisory is shared for download at exploit-db.com. This vulnerability was named CVE-2021-47764 since 01/14/2026. The exploitation appears to be easy. The attack needs to be approached locally. Technical details are unknown but a public exploit is available.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Exploit-DB (50511). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CNA Base Score: 5.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Exploit-DB: 🔒

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/14/2026 CVE reserved
01/15/2026 +1 days Advisory disclosed
01/15/2026 +0 days VulDB entry created
01/26/2026 +11 days VulDB entry last update

Sourcesinfo

Advisory: 50511
Researcher: Yehia Elghaly
Status: Not defined

CVE: CVE-2021-47764 (🔒)
GCVE (CVE): GCVE-0-2021-47764
GCVE (VulDB): GCVE-100-341332
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 01/15/2026 17:38
Updated: 01/26/2026 17:53
Changes: 01/15/2026 17:38 (80), 01/22/2026 05:45 (9), 01/26/2026 17:53 (4)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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