{"document":{"acknowledgments":[{"urls":["https://kb.cert.org/vuls/id/383864#acknowledgements"]}],"category":"CERT/CC Vulnerability Note","csaf_version":"2.0","notes":[{"category":"summary","text":"### Overview\r\nVisual Voice Mail (VVM) services transmit unencrypted credentials via SMS. An attacker with the ability to read SMS messages can obtain VVM IMAP credentials and gain access to VVM data.\r\n\r\n### Description\r\nVVM is specified by [Open Mobile Terminal Platform-OMPT](https://www.gsma.com/newsroom/wp-content/uploads/2012/07/OMTP_VVM_Specification_1_3.pdf) and is implemented with SMS and IMAP (and other protocols). VVM IMAP credentials are sent unencrypted in SMS messages. From [vvm-disclosure](https://gitlab.com/kop316/vvm-disclosure):\r\n> When a client sends any sort of STATUS SMS (activate, deactivate, status), the carrier will respond with all credentials needed to log into the IMAP server (i.e. username, password, server host-name).\r\n\r\nFrom section 2.1.1.2 AUTHENTICATE of the [OMTP VISUAL VOICEMAIL INTERFACE SPECIFICATION v1.3](https://www.gsma.com/newsroom/wp-content/uploads/2012/07/OMTP_VVM_Specification_1_3.pdf): \"The IMAP4 password is sent in the STATUS SMS message.\"\r\n\r\nTo intercept an SMS message, an attacker would need, for example:\r\n*   temporary physical access to the SIM card,\r\n*   to operate a spoofed a base station (cell tower), or\r\n*   to convince a user to install a malicious application that has SMS access.\r\n\r\nVVM IMAP services may be widely accessible over the internet or carrier networks.\r\n\r\nFrom [vvm-disclosure](https://gitlab.com/kop316/vvm-disclosure):\r\n> There is no indication on to a victim that someone else has access to their VVM. Android leaves their VVMs on the IMAP server until the client deletes it, so any VVMs on the client are accessible to a malicious actor.\r\n\r\n### Impact\r\nAn attacker with the ability to read SMS messages can obtain VVM IMAP credentials and gain access to VVM data.\r\n\r\n### Solution\r\nWe are not aware of a practical solution to this vulnerability.\r\n\r\nTake general precautions against SMS interception.\r\n\r\nIf supported, change your VMM password on some basis.\r\n\r\nDelete VMM data quickly.\r\n\r\n### Acknowledgements\r\nThanks to Chris Talbot for researching and reporting this vulnerability.\r\n\r\nThis document was written by Brad Runyon.","title":"Summary"},{"category":"legal_disclaimer","text":"THIS DOCUMENT IS PROVIDED ON AN 'AS IS' BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. ","title":"Legal Disclaimer"},{"category":"other","text":"CERT/CC Vulnerability Note is a limited advisory. It primarily identifies vendors impacted by the advisory and not specific products. We only support \"known_affected\" and \"known_not_affected\" status. Please consult the vendor's statements and advisory URL if provided by the vendor for more details ","title":"Limitations of Advisory"}],"publisher":{"category":"coordinator","contact_details":"Email: cert@cert.org, Phone: +1412 268 5800","issuing_authority":"CERT/CC under DHS/CISA https://www.cisa.gov/cybersecurity also see https://kb.cert.org/ ","name":"CERT/CC","namespace":"https://kb.cert.org/"},"references":[{"url":"https://certcc.github.io/certcc_disclosure_policy","summary":"CERT/CC vulnerability disclosure policy"},{"summary":"CERT/CC document released","category":"self","url":"https://kb.cert.org/vuls/id/383864"},{"url":"https://gitlab.com/kop316/vvm-disclosure","summary":"https://gitlab.com/kop316/vvm-disclosure"},{"url":"https://www.gsma.com/newsroom/wp-content/uploads/2012/07/OMTP_VVM_Specification_1_3.pdf","summary":"https://www.gsma.com/newsroom/wp-content/uploads/2012/07/OMTP_VVM_Specification_1_3.pdf"}],"title":"Visual Voice Mail (VVM) services transmit unencrypted credentials via SMS","tracking":{"current_release_date":"2022-02-24T19:51:20+00:00","generator":{"engine":{"name":"VINCE","version":"3.0.35"}},"id":"VU#383864","initial_release_date":"2022-02-24 19:51:20.333662+00:00","revision_history":[{"date":"2022-02-24T19:51:20+00:00","number":"1.20220224195120.1","summary":"Released on 2022-02-24T19:51:20+00:00"}],"status":"final","version":"1.20220224195120.1"}},"vulnerabilities":[{"title":"By hijacking a victim’s SMS for a short period of time (e.","notes":[{"category":"summary","text":"By hijacking a victim’s SMS for a short period of time (e.g. hijack the SIM card, MITM the cell tower, rogue Android App with SMS access), an attacker is able to gain permanent user access to a victim's Visual Voicemail (VVM) through the carrier leaking the VVM IMAP server credentials via SMS. After initial exploitation, SMS/SIM card access is no longer needed for presistant access. An attacker can now remotely access a victim’s VVM through the open internet (i.e.) and has the same access to VVM as the victim. This attack is often completely stealthy (the victim has no idea), and it is extremely difficult/impossible for the victim to change VVM credentials to prevent unauthorized access."}],"cve":"CVE-2022-23835","ids":[{"system_name":"CERT/CC V Identifier ","text":"VU#383864"}]}],"product_tree":{"branches":[]}}