Red Hat BusyBox TLS Parsing get_client_hello buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$5k-$25k0.00+

Summaryinfo

A vulnerability marked as problematic has been reported in Red Hat BusyBox. This impacts the function get_client_hello of the component TLS Parsing. Performing a manipulation results in buffer overflow. This vulnerability is reported as CVE-2026-88840. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as problematic has been found in Red Hat BusyBox (the affected version is unknown). This affects the function get_client_hello of the component TLS Parsing. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality. The summary by CVE is:

BusyBox TLS get_client_hello() reads past the end of the input buffer when parsing a truncated ClientHello message.

The advisory is shared at access.redhat.com. This vulnerability is uniquely identified as CVE-2026-88840 since 09/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/23/2026).

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

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

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License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

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

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

CNA Base Score: 5.3
CNA Vector (redhat): 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/10/2026 CVE reserved
09/23/2026 +13 days Advisory disclosed
09/23/2026 +0 days VulDB entry created
09/23/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: redhat.com

Advisory: access.redhat.com
Status: Not defined

CVE: CVE-2026-88840 (🔒)
GCVE (CVE): GCVE-0-2026-88840
GCVE (VulDB): GCVE-100-409077

Entryinfo

Created: 09/23/2026 20:09
Changes: 09/23/2026 20:09 (61)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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