Malicious PDF — malware analysis report

Static analysis result for SHA-256 79b7eedd38352e76…

MALICIOUS

PDF

75.6 KB Created: 2021-06-23 11:43:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: d47ece2aa3dba88065c3759fdbf91dbc SHA-1: 16d2afe748e3e12f2f6bddcfae51f17d207ab09a SHA-256: 79b7eedd38352e76bf870b9e19bba4e633245f79f98a9cd8a035f50c9b1de40e
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The document contains a link farm pointing to multiple compromised WordPress upload directories, suggesting an attempt to distribute malicious content or phish users. The presence of external URIs and link farm patterns indicates a likely spearphishing attachment delivery vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://studiopros.com/userfiles/file/ In PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/dc9tnpf0veuu5k5r8bt9n5682o/wupibiweberebifapirewupum.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/jn7h787r5jbctdj9psamu4rqm1/37982422324.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/9fb6d2a4a5ce8e0813108ecf99d4cade/zavowa.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/77750040623.pdfIn PDF document text
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/ga7seh55rla8m3pfcb551qnbup/97257745157.pdfIn PDF document text
    • http://ippon.lv/uploads/File/80934497599.pdfIn PDF document text
    • http://learningkey.org/userfiles/betepegasovugamumokelan.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160aaa20ab9119---nanuwebekipuzobi.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa79999e2a1---66695568815.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/muzoduwug.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160b6e3429d970---72371414398.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/1af31479004ae09a3c979bb0aaa0fd14/junukebewivubirim.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/g8ro4tdfgar0o4i1p5edvfrre0/rigabuwit.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/2b49gsabc50uctfbn8ja18njo5/jinizisoxane.pdfIn PDF document text
    • https://alutat.com/data/file/80794625642.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d1cb118b418---93594000364.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=best+worship+songs+to+sing+acapellaPDF 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD8B 5124 bytes
SHA-256: 18544dd991e5ee5fd37e5c5836d0615088e78a50005dadb1c82093fe5a4077c2
font_01_sfnt_off0000eefc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEFC 10540 bytes
SHA-256: ef1381ac8fd0973f1b579329452328adced731a890384089996bf810f16ca0a4
font_02_sfnt_off000112f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112F9 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e