Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2f690793540ee55…

MALICIOUS

PDF

84.1 KB Created: 2021-07-22 18:21:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0b473cf6bd8ab9b68495876b4a050fa4 SHA-1: e1f23f79ea1bc1ade05b288b8ba4c71533387e66 SHA-256: b2f690793540ee55da068ed9970d6c09ebae80e3b06b935db1a60d70840790ba
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised websites and disposable hosting, likely serving as a lure for phishing or malware downloads. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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
  • 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://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/a0a115c7408f8e5b7e5b75e22ca8b676/74949013236.pdf
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec7c871364---zilusodapobone.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6bba33a3b---52311153426.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/ntfarfdbdd77j34mvl0p9eci3e/nagujonoxararefokuzedezon.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071169600549---50558971355.pdf
    • http://bwc.lt/i/11058823615.pdf
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/opg58oaqd4bbicku91g5d289mn/benoxupewokek.pdf
    • http://primaneighbors.com/userimages/dumapawunuguxakal.pdf
    • https://istanbulbalbir.com/upload/ckfinder/files/1992055643.pdf
    • http://angarakshaksecurity.com/userfiles/file/52066907085.pdf
    • http://cephedanismani.com/images/pages/file/vedunipuvakatatitupif.pdf
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/8908v1k85aekg43bq7drs5uok9/rodapedefof.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f28ffe18bb6---duzesorofamidigonuvip.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c84aafe14---32752562840.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/5c4f6ce365e54d03fe4ff595bf29467e/folopapemuviponizexora.pdf
    • http://thaide.org/userfiles/file/82696998368.pdf
    • http://rc-modeller.se/images/file///85451030821.pdf
    • http://zatexpress.com//upload/userfiles/files/bigovonoponejorixagabo.pdf
    • http://www.socalgreatwhite.com/wp-content/plugins/formcraft/file-upload/server/content/files/160827596063e7---45508926978.pdf
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/pcoauc22olr7e5n0gng01ba889/pibedovepipa.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/6skmqlju0jfqilpnjgh2knc252/biwaguweke.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=case+study+of+student+pdf
    • 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_off0000e652.bin
4e389a1664af5a2f6ab9fe5bfb4122ebc41672879d5c3edc19ab37e3ec0c0bd4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE652 17196 bytes
font_01_sfnt_off00011350.bin
1f35c00f0d1562da33c3dce65bf9c97633c885eba18b1ffc21b3931e56441120
pdf-font-stream PDF embedded font (sfnt) at offset 0x11350 10500 bytes
font_02_sfnt_off00012b65.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B65 16792 bytes