Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cd96dd8099b4751…

MALICIOUS

PDF

76.9 KB Created: 2021-06-05 14:58:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 1658cde444d3b27e9ac62df16586963b SHA-1: 1a998f5bc8972ea41a12f4b44fa130e810c88e25 SHA-256: 7cd96dd8099b4751726cf4d2146b15721112f9bc88d7e4ed6a84b626314d9ac1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely to distribute a modded application. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically phishing or trojan delivery. The document body is heavily obfuscated and does not provide clear instructions, but the presence of numerous links on potentially compromised infrastructure suggests a lure for users to download further content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://krisoc.ru/uplcv?utm_term=space+ore+idle+clicker+mod+apk+latest+version PDF link annotation
    • http://altelaw.com/uploads/image/file/wabivigisivivuzuwanavuwe.pdfIn PDF document text
    • http://ciskmv.com/css/file/90427418929.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607341d1b2a78---lopenujefirifupomevajad.pdfIn PDF document text
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/0ac0d2d6385342337ec1a0b711eb0974/gajokopesinipuli.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b986517ca---53804677034.pdfIn PDF document text
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070bfe83bbfa---4062804472.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/9fdd6665c2dbcd300cf40204f38365a9/69909812077.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090553cb4ff7---mikokufeniguzu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5012e79fb0---kevegevuduluruguv.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/15ab10d0c5dd52781d8fd530293fa237/85154091637.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/68c51112d8ba07d1c5a886d064941294/xoxuzezoguxiv.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/nolasomimopok.pdfIn PDF document text
    • http://omonetach.pl/foto/ilustracje/file/53350151456.pdfIn PDF document text
    • https://securitydm.rs/slicice/file/14700154758.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/82401003140.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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
    • 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_off0000d969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD969 5448 bytes
SHA-256: 7d1c9e9c76709f780bc9ef4313fe0aa77914be9a88de7734c0f94cf533d3ff97
font_01_sfnt_off0000ebdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBDF 10144 bytes
SHA-256: b28a3de3fc70e58ad94f524b88d0942bb9e634cb0167c74c4992ef97f683ab75
font_02_sfnt_off00010ec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EC8 16140 bytes
SHA-256: 00468df452218f546d59995a7cf9b4297092e2fd476dbd2f6ce79846bd051107