Malicious PDF — malware analysis report

Static analysis result for SHA-256 77ee610611a0d79e…

MALICIOUS

PDF

87.1 KB Created: 2021-09-18 19:27:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d60ec5bdf0da1cd7f7ac5b793b655e55 SHA-1: f50533729ec63be31df5026d270b042f31259b9e SHA-256: 77ee610611a0d79eaf94e1fc6b8e1fc313787740963df96feddacc3af9dbe51c
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. The embedded URLs, such as 'https://crewmak.ru/uplcv?utm_term=wirelessly+connect+phone+to+pc', are likely used to redirect users to phishing sites or download further malicious content. The presence of numerous links and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=wirelessly+connect+phone+to+pc PDF link annotation
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8651a355e---xinisetivemuf.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/minobewafika.pdfIn PDF document text
    • https://norservis.cz/files/files/17445434125.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/jizakobexaxanuzizubobuw.pdfIn PDF document text
    • http://szkolaprywatnaleszno.pl/userfiles/file/dokovosotulegewir.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/96212224677.pdfIn PDF document text
    • http://packamate.com/userfiles/72975428641.pdfIn PDF document text
    • http://pazarziraat.com/userfiles/file/70017934153.pdfIn PDF document text
    • https://festival-bg.com/media/ckuploads/files/webamogorafalepukon.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/8eb75b81aa75b6df530ea59d4d751d72/kefikigurafizikan.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/3632966021.pdfIn PDF document text
    • http://risorsaterra.it/userfiles/files/42103864950.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/xelubizek.pdfIn PDF document text
    • https://calendarsunrooms.com/userfiles/files/15747595250.pdfIn PDF document text
    • http://dreamsurgeryen.net/ckupload/files/76335196014.pdfIn PDF document text
    • http://www.mostenpo.jp/userfiles/files/59094120463.pdfIn PDF document text
    • http://tns-china.cn/editor_upload_image/file/70309677253.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/63014476960.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/47577648782.pdfIn PDF document text
    • http://mtegl.wsystem.sk/userfiles/files/18060735736.pdfIn PDF document text
    • http://fpempresa.cen.es/userfiles/files/domemasokuxikag.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/37324319031.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/gobakonara.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/zeliropeti.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/tasurubis.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f0a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A4 10416 bytes
SHA-256: 50eaab3c4d20f842b7b8064ae443762dccd00f9a5c4f76ba35645a654cbcbcce
font_01_sfnt_off00010835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10835 18756 bytes
SHA-256: 5d31c828db5f1307011039b1e158e62133da15f44736f3add5afb975d8a69c34
font_02_sfnt_off00013704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13704 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1