Malicious PDF — malware analysis report

Static analysis result for SHA-256 174b07bc136eeb11…

MALICIOUS

PDF

81.3 KB Created: 2021-06-25 14:25:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 64ee1c44bc276320dfd4a0236f6d6aa6 SHA-1: f08241300d3582cad86ea28a2d98c27b7bd6dee8 SHA-256: 174b07bc136eeb1178d698b3b77bd10c2c3fc9720d8be7aa0284984f638febce
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised WordPress sites. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution via these links. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the link farm heuristic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/1f36ba2af4043e6c957806feb747c7dc/repomerifi.pdf In PDF document text
    • http://salkim.com/userfiles/file/tebinugajapox.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/mumazikedetefosi.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/ujm1qnqeickvq30e6hh5u6cugf/99564614622.pdfIn PDF document text
    • https://www.myosiaffiliate.com/199trust/img/file/87670460682.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/794b1a972983cdc5f30063b1175747dd/nojolujofivekidonilawerop.pdfIn PDF document text
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d63007e3ee---69208038485.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/584589b4f9ac8f758e55f56815ca5c3b/18485590623.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c85d1d43e79---91855068166.pdfIn PDF document text
    • http://aleeblog.com/wp-content/plugins/super-forms/uploads/php/files/m4kp8ri8fn378g48iji0qsq4v4/46691081502.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a272ae9faf2---xilizewig.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5cc344c3a---gimeroviredupurexipowisip.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abcda655f7d---69942819333.pdfIn PDF document text
    • http://talani.nl/userfiles/image/file/kuxifuripi.pdfIn PDF document text
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/80427897753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=subdural+bleed+on+the+brainPDF 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://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_off0000dd18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f52a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52A 16876 bytes
SHA-256: 081e5b570be69cf05ce0a921c56f03bd7596d432332b7ffc8bd6a3015526b715
font_02_sfnt_off00012104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12104 10492 bytes
SHA-256: f32ed8faaed649f767ce28956293baa3877881ac9cf0958565d1d91497b8d7b7