Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7a9157ca66690ce…

MALICIOUS

PDF

78.5 KB Created: 2021-06-23 13:16:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-14
MD5: c29b50a2746254895470ef6790138c68 SHA-1: cf57d20970c1f4b9465d20b2b932b60aef1c2965 SHA-256: a7a9157ca66690ce9b506146e4ec2b4b0fb929f05889a1d7b45c9497c49bd43e
156 Risk Score

Malware Insights

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

This 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 embedded URLs pointing to compromised WordPress sites and other domains, likely serving as a distribution point for phishing or malware. The presence of external URIs and compromised CMS upload links further supports this assessment.

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://philabc.ru/uplcv?utm_term=part+of+esl+crossword+clue PDF link annotation
    • https://www.skyline-recruiting.com/wp-content/plugins/super-forms/uploads/php/files/839ed6ec21e6e0d52fce3223a0b70cfa/2947063162.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/2645ffa541ce491daf4acad191687e1f/punerazetidinemito.pdfIn PDF document text
    • https://slaterlighting.com/wp-content/plugins/super-forms/uploads/php/files/dcd80b8d843f6ca08a3f0c3775334344/69150590538.pdfIn PDF document text
    • https://thietbidienmanhcuong.com/upload/files/vivikikuzukitaxax.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/4dde0d67a5468251cb899f9ccd0c5fae/69550013641.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea23705ff8---59459737121.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b162b84ba4e---46649342793.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/6qkbsvvc6gn09fs1o2lp4hh802/67111490939.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/c4c5ad1fbce1a9c11e64c6e485da2196/kijepivirabunuwewiteliju.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/b4lnusa9igdvgg8144qq79qe6c/sugivaxiguginawogodajer.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/56493658649.pdfIn PDF document text
    • https://motelandratecuci.ro/userfiles/file/6409183573.pdfIn PDF document text
    • https://coluer.ir/documents/file/84106505228.pdfIn PDF document text
    • https://dimensioninteractive.com/WYSIWYGImage/file/97760448784.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/2cfaa77483ed86c44f7297d91f07b399/23520382692.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
    • 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_off0000e8ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EF 4836 bytes
SHA-256: 32d35771703c2dabd100a85c75560f54d2e877e97eb0611c38f54c37544b24f4
font_01_sfnt_off0000f97c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF97C 11296 bytes
SHA-256: 0b7803021e1edb1df6c42d5441db917d2bd94eb1810d12dcbb71528fa47b7932
font_02_sfnt_off00011f0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0D 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c