Malicious PDF — malware analysis report

Static analysis result for SHA-256 7102fb6a877ce124…

MALICIOUS

PDF

95.7 KB Created: 2021-06-22 15:43:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 8813a107c25c06dcc3cc4b4d32e54ebb SHA-1: 172540f62f884c83bbfb7133fd620aeb647501ed SHA-256: 7102fb6a877ce124152b2f931da78f0b43ecca9946ebdc9be9f8e28a0e973576
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, indicating a likely attempt to manipulate search engine rankings or distribute further malicious content. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted, and the document body was heavily obfuscated, limiting further analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609410f98ec26---nujirewewadolarixajovifa.pdf In PDF document text
    • http://bularz-auto.pl/images/userfiles/file/81309675424.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160948f4a00951---35322178474.pdfIn PDF document text
    • https://egyiksem.hu/uploads/file/26614675659.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/18963505919.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/16081207b5cf99---gidijapusatokizebiwadozab.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/f7krd1j2j6nf522vr609rkd0o6/41190878838.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/dcaa594474eb4f1540c10474f6fbaac6/takik.pdfIn PDF document text
    • https://area5srl.it/file/wuxelikakupixow.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/v5m8njb6k753i7v59gdqhqmct4/4258168787.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/42273457713.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/42bab9f754db747136791748b64274e7/tobawojebapa.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c147d5de06e---wojilugosopepepobef.pdfIn PDF document text
    • http://kawoka.com/userfiles/file/tevoxino.pdfIn PDF document text
    • http://devison-matras.com/upload/file/maronat.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/zexobenop.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/18a8f7f7fa0798dabb7b431941deb23a/wutegikudobupumaronuwevaw.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/88830128503.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/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=the+permanent+instruction+of+the+alta+vendita+pdfPDF 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_off00013bf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BF5 5404 bytes
SHA-256: 6e587ff139c1285db546519c1ba32bd9dac3a00cf4d9655557fbd789837774ef
font_01_sfnt_off00014e30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E30 10376 bytes
SHA-256: d82473e04ac3e796b4cf37945080b029fa6573b96d7a3e4bf29e6068126a5df8