Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab75c63df0fe91ab…

MALICIOUS

PDF

77.1 KB Created: 2021-09-17 22:56:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 779b5b0327b51b392667881b4be22150 SHA-1: 52264f5dd31445daf1046ca144a3469b2be43ffe SHA-256: ab75c63df0fe91ab3acb56669d3f22c0f292265f8b7efc19a5d6bf3ed62e56a9
156 Risk Score

Malware Insights

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

The PDF was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URLs, many of which point to compromised WordPress upload storage or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing lure but serving as a container for these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://irlanc.ru/uplcv?utm_term=i+forgot+my+swipe+password+on+my+android
    • https://speakingparrot.com/upload/ckfinder/files/jolesururuxofudid.pdf
    • http://keramann.ru/uploads/files/70894686764.pdf
    • https://hopclickhospitality.com/scgtest/team-explore/uploads/files/sumodugexanobomakufemi.pdf
    • http://mindennapi.hu/upload/file/35926682510.pdf
    • http://maiodi.com/userfiles/files/96933779986.pdf
    • http://qhchemicalsfeed.com/upload/files/lirugow.pdf
    • https://trouver-une-ssii.com/img/pics/files/vaxoleviwubutafitobomexop.pdf
    • https://deewo.de/wp-content/plugins/formcraft/file-upload/server/content/files/161428306485dc---78377454694.pdf
    • http://www.kymenhome-etsinta.net/tiedostot/files/viwipuvat.pdf
    • http://gidromall.ru/img/uploads/file/21270297618.pdf
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/67680450605.pdf
    • http://akatumusics-ang.communication-pro.fr/public/1283/contenu/file/23306328677.pdf
    • http://francescasciortino.it/userfiles/files/47033297296.pdf
    • https://newtop-eg.com/userfiles/file/sisisuwoguzobi.pdf
    • https://bostaninsaat.com/image/files/jorepobipa.pdf
    • http://bscsaoner.in/ckfinder/userfiles/files/kiwok.pdf
    • https://ln80.cn/filespath/files/20210904140720.pdf
    • http://enjoybowlramenandpoke.com/uploads/files/refamejemowezef.pdf
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/161403edfeb674---25202328071.pdf
    • https://macroedunet.com/userfiles/file/72321537015.pdf
    • https://asztromiskolc.hu/ckfinder/userfiles/files/vuvaxojozo.pdf
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/vedunabelogi.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/b61e80b638bb347cba6591cc70e87d4e/nadusarijovemuwofamexo.pdf
    • https://jetaime-shop.dvsportbg.com/files/xobixebomuwuponebigeze.pdf
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/161390524d8549---kirotodidipefarijisulupaj.pdf
    • http://iktoktatas.hu/files/file/40807979056.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_off0000c812.bin
26d67ed4e78966c987fb9152d9ee1804d6a0c76dccd01b15b2b1d3956b6b71da
pdf-font-stream PDF embedded font (sfnt) at offset 0xC812 10948 bytes
font_01_sfnt_off0000e15a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE15A 16792 bytes
font_02_sfnt_off0000f96c.bin
33fa958ab309b1a3db47e807886701228ce70e86d3e69f6ca33a8128fb9d4f4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF96C 17260 bytes