Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c0be6e7f013579c…

MALICIOUS

PDF

88.4 KB Created: 2021-08-29 08:59:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a8f7f43abb67d71f28d0d8352924c06 SHA-1: 1b284c4896d38f171798b87f4b3f840bd11b1f9a SHA-256: 4c0be6e7f013579cc2abeed6bd0175a2dd7735441ae01d1c0a62200477163333
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a phishing or malware distribution attempt. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

Heuristics 5

  • 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://cructi.ru/uplcv?utm_term=wppsi+4+subtests
    • http://www.ambatownship.com/ckfinder/userfiles/files/bagodonakifobozuwan.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608e175559055---vejapukurisizusetikiw.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085ebad85e72---89929676134.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ee81c44575---33293255133.pdf
    • https://houstoncoinclub.org/FCKeditor/file/doriboferemuvido.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607aad710d362---dikosisesuwijujox.pdf
    • http://www.alquilerbares.com.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16075e97bee3d6---zegikunewuzofukuj.pdf
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/kn7t0e0mdb83a4pbaav3s76vln/mutiw.pdf
    • http://askort.pl/Upload/file/subimuw.pdf
    • http://jakpaisanestate.com/images/upload/files/sifovudisefu.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16109b4d1eda93---pelavosamimame.pdf
    • http://ck-tct.ru/userfiles/file/galuwezazefezuwebexamu.pdf
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/7fdc628419440c2eb44d9a7ba9ef657a/wosamopotalitarotipamaw.pdf
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16104c746e4079---41306285973.pdf
    • http://billsky.ee/files/file/peveso.pdf
    • http://clubesquilacoma.com/uploads/files/fonexe.pdf
    • https://www.audioclinica.pt/wp-content/plugins/super-forms/uploads/php/files/ghpk4l40qbvle70vje61t05rqm/79963788559.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077f0d483501---kedug.pdf
    • http://surmounttravel.com/userfiles/files/felovegirerefesowado.pdf
    • https://elesud.it/img_pagine/file/lopevuv.pdf
    • http://ciskmv.com/css/file/guwezugufosugu.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612a113a4e331---dodenevasavijapifipesasu.pdf
    • http://kiiga.ru/userfiles/file/jexutu.pdf
    • https://dbjadow.pl/attachments/file/bujuzenebulopodovapa.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_off0000f462.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF462 16792 bytes
font_01_sfnt_off00010c79.bin
41407ce351312b75af508612355bded35306c73cfe242093a0b2589cdf45e534
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C79 10024 bytes
font_02_sfnt_off000122b3.bin
e27bbca0f43745b1587bf939ebc2f4b872948c29d9104af46d6e2a9b3b6a5e16
pdf-font-stream PDF embedded font (sfnt) at offset 0x122B3 18500 bytes