Malicious PDF — malware analysis report

Static analysis result for SHA-256 77fd47ac13b126b2…

MALICIOUS

PDF

71.8 KB Created: 2021-05-02 09:17:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: a9137c05dba996d35b0c1e329bdc0f8b SHA-1: 032442ac653d948f31daded722f107e57ed25292 SHA-256: 77fd47ac13b126b2366adff5882d971c73d020cfcba9486457ee467cec0f0a0c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting it's used to distribute further malicious content or phish users. The embedded URLs are likely part of this distribution or phishing scheme.

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://area34.info/wp-content/plugins/super-forms/uploads/php/files/p0lqlc93fpbgv7qcmokvcrgj91/27513826123.pdf In PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/4fj0e2199o1gjff4tf16iejis0/68154513886.pdfIn PDF document text
    • https://tlpnw.com/wp-content/plugins/super-forms/uploads/php/files/3cf67323ad63be48b24772df362666bf/3853747266.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16072923661d06---dirowarivitokiwor.pdfIn PDF document text
    • https://lion-trading.co.uk/wp-content/plugins/super-forms/uploads/php/files/ga32s3o1cs7i57cnmqb208cgjl/96439729074.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/d6784aeca664ceb7e1dc59bf632007af/22793725199.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1607aafe39bebf---61794066982.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/e5m0jnhrl06narjjfnmqug7cj7/wewedivowaribesax.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad265240e9---xapenamowipuv.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/935e9c8eeffd6c73f65e9a50527b0fc1/fifopifozusidatiridezuve.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607da24cbd669---89302091274.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089f6c9843c6---77281226101.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/d02af11fdf1190e749945bf57d5f82b7/4702588982.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16083441d5b9ee---motimajijimaw.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/g93lg9giglv3rr29mrvkm31rmf/dadutozajuzepege.pdfIn PDF document text
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/f1v7oe33a7ofcmfaev8qe6hiud/44005947243.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160747a4035db0---60525050689.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=linear+equations+problems+worksheetPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBFF 5420 bytes
SHA-256: bbe8ac5c87b17ad390e340347f396cb7ee59cf27abf3e2838489f720c62703db
font_01_sfnt_off0000ee58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE58 10700 bytes
SHA-256: d78e7f8bfda01b3a47437698126f2080826bc7c58e9e0c394e70e2c49a44f151