Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac5c9a9d8eeef8f2…

MALICIOUS

PDF

82.2 KB Created: 2021-06-29 22:44:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2282dd59ffb5bef597260480fef65a81 SHA-1: 6efbecd3620239aeccf39c7fcc11300d0d8e06b2 SHA-256: ac5c9a9d8eeef8f2c79ff2265caf6948d8cd384779a0c948ab37945db30ed510
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to other PDF files hosted on compromised websites, indicating a link farm or distribution mechanism. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were directly extracted, the structure and URL patterns are consistent with malicious PDF lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160856ac120483---98000636484.pdf
    • http://andlupa.com/userfiles/file/66987784691.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcedc49614---vuvurivewazaja.pdf
    • http://falconartistmanagement.com/ckfinder/userfiles/files/subekariwuzof.pdf
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/2b753729fea4dcbc28b853096bb6f1f8/88144900503.pdf
    • https://codecs.ro/images/file/33476403657.pdf
    • https://mygo.com/ckfinder/userfiles/files/kepebiforefefes.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608d3f790e65d---padoxawikuzedeseze.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/68s24ufdsr5r5lj2idnlraammn/88679780396.pdf
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/a4da16c28a6c39025b3aacfdc4f6ca12/492517312.pdf
    • http://zpb-maciejewski.pl/upload/fck/file/48006325789.pdf
    • http://allycatering.com/userfiles/78097647726.pdf
    • https://inclinedigital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076a1fc29eb0---75446612267.pdf
    • https://didacostruzioni.it/userfiles/file/29204815456.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/2726a27f39ed553443e7e98fa12fdf21/fitulobin.pdf
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160ada107886a4---tikuwobafoxo.pdf
    • https://ecomassage.pt/wp-content/plugins/super-forms/uploads/php/files/n8ourc4temm2d6jhsb1j6j0cd6/gotodojariv.pdf
    • http://diamantina-joaillerie.com/ckfinder/userfiles/files/zijuzom.pdf
    • https://tonwen.org/userfiles/file/sememumesawusij.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/aaf759b8290186c94179844fbc9e16e5/gojelowivadodivo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=enthalpy+definition+in+chemistry
    • 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_off0000dccb.bin
9f4b9a2f7ade935a072e62ca61c976acdd17caca862dc63ab64c03a9a8412bf2
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCCB 17560 bytes
font_01_sfnt_off00010ac5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AC5 16792 bytes
font_02_sfnt_off000122dc.bin
77c53cc5340e6ea670a6d36e427007d5d25d252d9b450573d59996bcb690f0ad
pdf-font-stream PDF embedded font (sfnt) at offset 0x122DC 10980 bytes