Malicious PDF — malware analysis report

Static analysis result for SHA-256 edfc8c842bcfe868…

MALICIOUS

PDF

89.7 KB Created: 2021-09-21 04:20:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: abb28768d704d2aefa24182dfa4d89b7 SHA-1: b0c13e82df2632bc6853b64ff0c666dc0915b098 SHA-256: edfc8c842bcfe8689b56f51d4776fe1c28b0b93e56ba44ced07d4e103e158c60
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting it's used for SEO manipulation or to distribute further malicious content. The presence of multiple PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://dfanchem.com/upload/files/vapoporururofu.pdf In PDF document text
    • https://lidiyageorgieva.com/ckfinder/userfiles/files/47502061003.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec34a4dae2---95566028649.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/14294585609.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/96002674873.pdfIn PDF document text
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/28545249794.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16131fb0246d80---79436535777.pdfIn PDF document text
    • https://www.channeloflove.com/ckfinder/userfiles/files/buxokefununakitirun.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/21785900968.pdfIn PDF document text
    • http://d-a-s.cn/userfiles/file/79232610432.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613485481b553---dajojik.pdfIn PDF document text
    • http://irinabailey.com/upload/files/jexokizuju.pdfIn PDF document text
    • https://esz.jp/img/editor/files/14697329898.pdfIn PDF document text
    • http://balcimimarlik.com/resimler/files/fuvilesodudulavade.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/98ec1772027a6aed6c429c57fa5a24af/kurekumokofom.pdfIn PDF document text
    • https://tekdalyapi.com/upload/ckfinder/files/43116424341.pdfIn PDF document text
    • http://abnig.friendship-match.com/upload/files/nigesofagulodisugawosut.pdfIn PDF document text
    • http://affectif.ro/data/Image/file/56903164522.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/84091029991.pdfIn PDF document text
    • https://edinburghpools.com/contents/files/74189004749.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/bitixaliromonivomen.pdfIn PDF document text
    • http://cen7dias.es/userfiles/files/xulasizawava.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=how+to+use+phone+as+touchpad+for+pcPDF 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://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_off0000f832.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF832 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11049 10756 bytes
SHA-256: fcc079a76d245b98f0e6d79092ab8fb3d91447e56f183cb3a7f2f5dcddf2a9a7
font_02_sfnt_off00012903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12903 18528 bytes
SHA-256: d7b0962a195d7a877dae5f5fdd1a94540dbb0f782371616845dfef5dab7a41ac