Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c5152db3076c618…

MALICIOUS

PDF

86.5 KB Created: 2021-06-27 17:06:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0ca4b2abc931a63f9508e53cc755b45f SHA-1: 379e6ceaaf599dbaaa4020462bd374c112e90363 SHA-256: 3c5152db3076c6185123ab69488b86d1f9364313335bbbeb3190fbbb37c82bea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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://sashtraayurveda.com/ckfinder/userfiles/files/tudukozakibod.pdf
    • http://fence-alarm.com/userfiles/files/busuberazurezavirezutinaz.pdf
    • https://ozmutludokum.com/userfiles/file/lixadelove.pdf
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/th4f06odvf8kdkuruvr8kpd2ic/82960129552.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bad2d8e28da---gitisavo.pdf
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ded712df27---muxagosekonigomazo.pdf
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f25139a6ff---96614902117.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/b72af010f3af28565567894eb82e2212/24939428444.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/85b24e06b8e009710a33c4974ae50280/xubuwazodo.pdf
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a10a1f84763---40159824866.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ba15d33b7fa---15829985668.pdf
    • http://seritour.com/rsm/files/fidukakevifokarubejazeref.pdf
    • https://hantverkarenisandby.se/UserFiles/files/99071080110.pdf
    • http://www.klccpa.com/userfiles/file/
    • https://digireg.cz/upload/xedana.pdf
    • http://bertrandetgastineaudesigners.com/userfiles/file/rexumu.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609bc281bbe1c---jizapujurinuzapeluwu.pdf
    • http://clinicaveterinariabilancino.it/userfiles/files/wamiwuzevetire.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608afb9ff3418---77164265980.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=holiday+bernese+mountain+dogs
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ee4b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE4B 16792 bytes
font_01_sfnt_off0001065d.bin
9c3063833ab0e4997c52607407ed1b0cfad1ad5000a5af94a767f6123bd62f2f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1065D 17444 bytes
font_02_sfnt_off00013421.bin
0ef07a4e58e6327f58a2703639aba210165f19bcddaf3cbc20311a51cbcf1ebd
pdf-font-stream PDF embedded font (sfnt) at offset 0x13421 10936 bytes