Malicious PDF — malware analysis report

Static analysis result for SHA-256 57825d2bcc033eb7…

MALICIOUS

PDF

72.6 KB Created: 2021-09-14 18:18:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: cd784414247db759aed46a938c382963 SHA-1: 410168fa7e155bfbec9ea2b61eb0975787c58811 SHA-256: 57825d2bcc033eb7b77c72b36347d0b5333979d13f640a3c36d7a73b12217f51
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of multiple external URIs suggest a tactic to lure users to malicious content, possibly for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crewmak.ru/uplcv?utm_term=max+payne+3+game+download+for+android PDF link annotation
    • https://dobski.pl/userfiles/file/zuxul.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1613fcfb2a202e---25487641765.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/58573152814.pdfIn PDF document text
    • https://goez3.com/10005001208290177/ckfinder/userfiles/files/tuserux.pdfIn PDF document text
    • http://dralituncer.net/userfiles/file/30655729259.pdfIn PDF document text
    • http://wolfpackbasketballacademy.com/content_docs/xerirul.pdfIn PDF document text
    • https://olgunbey.com/upload/ckfinder/files/35575987553.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/82772685591.pdfIn PDF document text
    • https://comptables-publics.fr/userfiles/file/dotufulokused.pdfIn PDF document text
    • http://vina2002.com/uploads/files/99539607761.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/mogilorodadotiduj.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/r4m8iqfm1pdtaoco4c95k4smv2/24662914106.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/h2iaplbob2pup4rb960qr1dv6b/xusanulefazifaroletakizol.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/fubodon.pdfIn PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/xenovujovuga.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131d403dbe67---30099472591.pdfIn PDF document text
    • https://pui-vital.ro/msg_media/file/95983677439.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/84805986679.pdfIn PDF document text
    • http://makrostal.pl/user_images/file/67630681672.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/8770842795.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136fc9440e8b---rebenubifuganujumoroti.pdfIn PDF document text
    • http://lpc2529.com/piceditor/file/62531661302.pdfIn PDF document text
    • https://www.groupe-coelho.fr/ckfinder/userfiles/files/22898602485.pdfIn PDF document text
    • http://fullx.net/files/40986394308.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/9161271667.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_off0000bbd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBD0 15440 bytes
SHA-256: b85c8994fea2dd0e576c0d2a1e2d4ac82972a3f5d5fc34f87577a5b5d8e33dce
font_01_sfnt_off0000e305.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE305 11040 bytes
SHA-256: 45d48647e1c1c37e5a2a36be5eeb015ee72b198d75f3bf8a87b0721cbdf20612
font_02_sfnt_off0000fc8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1