Malicious PDF — malware analysis report

Static analysis result for SHA-256 a79b4783976ae170…

MALICIOUS

PDF

125.6 KB Created: 2021-06-25 14:10:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f00bcc6d40256c26735b46a4bcaba6fa SHA-1: 7f417b938a825ca09ff2b2656c0764f9ca76c948 SHA-256: a79b4783976ae1709ea3631db2dcfa725c5223546873fd6c39e330b142546842
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised WordPress uploads and other potentially untrustworthy domains. The primary attack pattern observed is the use of malicious links to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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 https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/7932b88d7d50e4ebe4b8c82ce0880651/vumofitozeluxij.pdf
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c18f1d97844---17646251170.pdf
    • http://ediljolli.com/userfiles/files/22036444384.pdf
    • http://vogiantinhmach.com/media/ftp/file/11635582131.pdf
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b7511e902fd---85199800455.pdf
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1608ec69fe195c---91617294666.pdf
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3db63366d.pdf
    • http://jandebruijn.com/uploadimages/files/72800707099.pdf
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cac96afa0c---44140623117.pdf
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607208a4a66b0---pokatamawuzomijopifeg.pdf
    • https://oversaslogistica.it/file/lerarexarimuxawuja.pdf
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1f94edf794---31236074519.pdf
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cc96012901a---kefufofewamigi.pdf
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092fa8f59969---lubelasasulivolupe.pdf
    • http://techbico.vn/uploads/image/files/33709514403.pdf
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/a49cc94952d0ac162ea7a9421186e791/44695058530.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=l+childhood+death+note
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000172b3.bin
aeec65ab1ee203720705b4e93c0fc9f51687011dddf5814b2a71210951c72fc7
pdf-font-stream PDF embedded font (sfnt) at offset 0x172B3 10156 bytes
font_01_sfnt_off0001894e.bin
2e4d838ca9999a95ddd1ac08a96794772301184a65802f9e41dd58f51933809e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1894E 20612 bytes
font_02_sfnt_off0001bced.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1BCED 16792 bytes
font_03_sfnt_off0001d4fa.bin
2dce01dd10a2995539abd98e98ee3ce860fb5b5cbeb84843a838c912fdd27db1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1D4FA 5612 bytes