Malicious PDF — malware analysis report

Static analysis result for SHA-256 635bac6bb57ec1ce…

MALICIOUS

PDF

75.8 KB Created: 2021-09-04 05:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f8f5756b7bb0ddf938bed7cb1a9d3429 SHA-1: 07940f97b41284a270fcf7ab2550a2ab262a907a SHA-256: 635bac6bb57ec1cea99ac863c7ef077c1512c24810cff450904eaf37250f4e0f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm or phishing lure. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to redirect users to sites hosting malware or phishing content. No scripts were extracted, but the overall structure and URL patterns are consistent with a malicious PDF designed for initial access via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://laborke.ru/uplcv?utm_term=handbook+of+adhesives+and+sealants+pdf PDF link annotation
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/05ab7030fdfd7a9bb6a680f6bfe0d6ec/rofivizili.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/79184086888.pdfIn PDF document text
    • http://enricobarraco.com/files/45215666793.pdfIn PDF document text
    • https://bleikss.com/userfiles/file/49132532552.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/3198f5b64f119a8bce7544b9dd000df9/xamenamipeb.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/h3pg2imu0oudsdcv3v4p1og7la/nulodopedob.pdfIn PDF document text
    • https://olympicwroclaw.pl/zdjecia/fck/file/13399421595.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/56fc78bc8a4da38d5050f77c53d14f1d/41576744848.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/160f2a781c9da8---7540226799.pdfIn PDF document text
    • http://plan.msu.ac.th/ckfinder/userfiles/files/ganelufoludumu.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/53f88c4487f931402db729bfb7c651e2/67115905617.pdfIn PDF document text
    • http://shinex-auto.com/userfiles/file/35617166149.pdfIn PDF document text
    • http://fornacedelia.it/userfiles/files/milutopuwomivalexezuwoj.pdfIn PDF document text
    • http://cmtdental.com/upload/ckimg/files/losevisironuz.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606f03f592c2c---zabikumupotasirogedadu.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/77536f72d9ee23c109f76558d45fa662/95510443996.pdfIn PDF document text
    • http://mamam.by/upload/File/file/fobelaviputu.pdfIn PDF document text
    • http://westmoorclassof1965.com/clients/5/52/52ec68f2b927accf75267cb07bfcc891/File/nizabaduxurowowe.pdfIn PDF document text
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b2b988b0bd2---tejefuxubagure.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f252f7a806---vadigesifap.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/0b6f04ec4f112042a89b4d043ec9eb96/xerajex.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/8de0d249fb08920bb3051decab45ad60/20010271316.pdfIn PDF document text
    • http://seamacros.com/upload/file/dijilerefebabot.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160891c66c0541---58004233686.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/5b8f13d4b5a79ea6720657cb43adeea7/posozasus.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_off0000c6e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000def3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEF3 16384 bytes
SHA-256: a2a87053daab2f55ce3505d2ea27c04f7bcd16f33b79178acb6a40ba725531ea
font_02_sfnt_off000108a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A5 10784 bytes
SHA-256: 3590e01ae257067137f76629f790b0d93268a01957f653adee41c3f1ce05e582

Open this report in the interactive analyzer, or submit your own file for analysis.