Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c5291cc4b412633…

MALICIOUS

PDF

73.8 KB Created: 2021-05-30 09:59:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 2da5ff30088207e0f143e34dfd7a4f1c SHA-1: 9a58aa8b6fab5796c12699affe9abec9c918a9d5 SHA-256: 8c5291cc4b412633e0821ec8bb3ae6a4be2aa03c2d98d55f6bae79fd556d5a6c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to compromised WordPress sites and disposable hosting, suggesting it's part of a link farm designed to redirect users to malicious content. The presence of embedded URLs and the PDF structure strongly suggest it's used as a lure in a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://acethamessecurity.co.uk/wp-content/plugins/super-forms/uploads/php/files/8c60e0471c0d6d2789963118be4e45b9/91086610808.pdf In PDF document text
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e1bf1c8f07---petowijenaxogogude.pdfIn PDF document text
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609eef1fb1967---dazifikose.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606eb6083a9e2---fetudepaxobureburuges.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/970661a691c2b7702c2b98958f9f17f8/zuloxo.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/02430780aef0689f0ab2d7bcadf02520/wudebiwetoril.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5eabcafc0---55477871537.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/60777814580.pdfIn PDF document text
    • http://nutricion-intravenosa.com/wp-content/plugins/super-forms/uploads/php/files/384862989db57939448c4bde452897c2/82207628181.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/79613651827.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806aff09dd3---lijitirurew.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16084f08b9c906---pejudemepivawavul.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a99fcb37e17---zeponoruxuwopiwadazoboxa.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160799a77ccd31---18478032795.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fca0828907---mozefawadewifuvaj.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/e0ada1d547a8835ce420d492092c9ff5/nenaxijawajuneb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=is+broccoli+allowed+on+hcg+phase+2PDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e33b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE33B 5636 bytes
SHA-256: a2423eb2be2e3fa552b785963d0e7a9f71852e86ccb712864ce2fe1f5fbb45a7
font_01_sfnt_off0000f669.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF669 10556 bytes
SHA-256: f94a1fc4425776db17f5721bc5ca1c0f29c8ded8da4cb456f32b57beeec31530