Malicious PDF — malware analysis report

Static analysis result for SHA-256 8160100d88673170…

MALICIOUS

PDF

84.1 KB Created: 2021-06-25 12:09:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: c39af73b43bbd857ea513f0374152313 SHA-1: 0d33e62bce2144e84a52c49014ab707c47eac56c SHA-256: 8160100d8867317000255449c58037ac4549ec98614400481f6883ba8a0447ad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs suggest a link farm designed to redirect users to potentially malicious or phishing sites. The document's structure and the nature of the URLs indicate an attempt to exploit search engine optimization or to host deceptive content.

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 https://cructi.ru/uplcv?utm_term=how+to+save+webpage+as+pdf+in+opera PDF link annotation
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9bd3ab5d6---xazirarofuwud.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/52931706952.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/j9e2hts8h21cc3cgriefpiuevj/22446879713.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/jitukijukoluruledukufezug.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a08d69c5a93---43137132795.pdfIn PDF document text
    • http://intestinalfortitude.org/clients/0/0c/0cf504f131cb0201443a7bd449519f4a/File/69899462291.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/cndb9fkosqraermfsas6q9mse6/jozuwojarebonekezigaz.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/65032389468.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/beramilifeguwabarejanunum.pdfIn PDF document text
    • http://surtek.biz/image/files/20150121_132909.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c51059f396b---38663971805.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608c561712254---20854778943.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/eaeb07c2b75922232e33e3db073aa62b/3694602563.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/divaxotiv.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609eba587789b---wavavuvalonukatikuba.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/lazapolawi.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B6 16260 bytes
SHA-256: 1d1111ab8f9ccc6407e114dde1f541053317dc2d99610714b401846097146e08
font_01_sfnt_off000112b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112B6 10912 bytes
SHA-256: fa6199b212d9acb77e8422f1e50d27c2843a826edc9849131fc9b99eff0322bb
font_02_sfnt_off00012baf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1