Malicious PDF — malware analysis report

Static analysis result for SHA-256 c438b40b25f925a6…

MALICIOUS

PDF

96.1 KB Created: 2021-07-13 00:03:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: eb2868b88605a54cc50ac789d53cf0bb SHA-1: ab8e6f98de7e48e8f66343d551cdb374601738e6 SHA-256: c438b40b25f925a67afa3e682c459f8d32b6450151f92a0e5acd627c7fa4fa0e
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, but the link farm structure and compromised hosting are significant indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/9354f73ec78b418f548cc20e6a372367/jizemexigosoluk.pdf
    • http://50wj66.com/clients/a/af/af9d65f11c1965a5434adcd4cd578f00/File/jefagufajoraveburudupu.pdf
    • https://htchninc.com/d/files/zogulapisegufiroz.pdf
    • https://grupo-kayros.com/userfiles/file/xopeparel.pdf
    • https://pacpartner.net/images_client//imagesfile/kemewonadisetafotejige.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/38110f28aa1eb454c2e6d922c2a8ce2a/47850076907.pdf
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a537402da60---10867773116.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606c83cb9e95b---16848917085.pdf
    • http://cuacongtrinh.vn/upload/files/bogusemopibowilujox.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/r0b0rqs0tglmittbki6kcnlfh2/65743279210.pdf
    • http://samrayburnclassof1980reunion.com/clients/873185/File/43378985389.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160b7ff686b76c---potilojal.pdf
    • http://cycling-software.com/files/file/wawozuvujege.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee245a5474---21736357798.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/9sbfathicdde6p54g5nkblllot/83153781029.pdf
    • http://terezmisszio.eu/files/file/37320520979.pdf
    • http://triatlonbizuterie.cz/sites/default/files/file/wesotobetijozalolasowur.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16074022e7ba36---zapij.pdf
    • http://mountcalvary76.com/clients/9/90/9062e1c9f2360b2cedac6e2854879500/File/debaradobume.pdf
    • http://americusfelderfamily.com/clients/0/0c/0c5e5e27a4da9db51eb23c24aa0fa274/File/setarir.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=variable+resistor+ltspice
    • 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_off0001127d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1127D 16792 bytes
font_01_sfnt_off00012a8f.bin
36440279b102ea436d45eb80da43942110d96760cfa722a92dde02fa497b4b6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A8F 18864 bytes
font_02_sfnt_off00015bf2.bin
a2cbd265404543d0bc80c6e1a3b9cefc1e51d42728ee95d93bbd919928477d37
pdf-font-stream PDF embedded font (sfnt) at offset 0x15BF2 10372 bytes