Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f88317a02d44d2c…

MALICIOUS

PDF

67.9 KB Created: 2021-09-26 10:51:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9aa6817b03e13bf86d8fc74893698175 SHA-1: 77cc740fda7b38376ee325285f5b0cc67459767b SHA-256: 6f88317a02d44d2c091c883098618430d8a8f03a54d83ea8e2439d2ff8b1f9be
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The 'SE_CALLBACK_LURE' heuristic strongly suggests a callback phishing or tech-support scam, where the user is prompted to call a number. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or social engineering attack, likely involving the download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://bk-plus.at/userfiles/files/4347824923.pdf In PDF document text
    • http://atek-ent.com/upload/file/wotiravetanerirexejuxut.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/59516066374.pdfIn PDF document text
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/kakonisupopo.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16143bb47144d3---zirotapaludokezazotudegux.pdfIn PDF document text
    • http://bakoca.hu/files/file/81942043422.pdfIn PDF document text
    • https://socardan.com/userfiles/files/mubun.pdfIn PDF document text
    • http://korea-seals.com/ckfinder/userfiles/files/52454052924.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/b0fdcu0ibgkpsin3igm2tgur85/94498591112.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/71053240252.pdfIn PDF document text
    • https://ajansnigde.com/resimler/files/81896767749.pdfIn PDF document text
    • https://dentalrud.com/userfiles/file/52055021534.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/buvegibewumaw.pdfIn PDF document text
    • http://avandcie-automation.com/ckfinder/userfiles/files/lawuwobew.pdfIn PDF document text
    • http://happinessgown.com/upload/users/files/91571912161.pdfIn PDF document text
    • http://heatexchangersolution.com/upload_fck/file/2021-9-6/20210906034758181307.pdfIn PDF document text
    • http://dinobajka.pl/Upload/file/59538405267.pdfIn PDF document text
    • https://btegypt.com/file/mugawu.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/lupotivilinalew.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210905032018.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/dopisuketakimopos.pdfIn PDF document text
    • https://malinaionescu.ro/userfiles/file/mikudekuten.pdfIn PDF document text
    • http://i-daa-wl.de/userfiles/fanolavaxisag.pdfIn PDF document text
    • http://stilna-ya.com/_userfiles/file/16956474927.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=the+theory+of+everything+piano+sheet+music+pdfPDF link annotation
    • 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://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_off0000af29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF29 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c73b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC73B 14748 bytes
SHA-256: eea802fce106bd77cb98a9575855e1eeeb572e27ab86ffd9ff3ba6584b25061b
font_02_sfnt_off0000ebf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF9 11264 bytes
SHA-256: 50ffcfc0d013852774194d394b7a657b21ab4c75c05c4a733a010f8fb4f80eb5