Malicious PDF — malware analysis report

Static analysis result for SHA-256 a880da9550a70e02…

MALICIOUS

PDF

76.2 KB Created: 2021-09-08 05:29:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b598d877b0cd874380f5f3667e59ad16 SHA-1: 6f0554a84c15fa312f85d48d5c6cf6af736b9c75 SHA-256: a880da9550a70e023ac54e4a3043c419cf59f26587314a0de17eb11d7df54fdc
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://akicgiyim.com/userfiles/file/70381247998.pdf In PDF document text
    • http://letdentalab.com/img/files/86886390093.pdfIn PDF document text
    • https://digireg.nz/upload/63118530061.pdfIn PDF document text
    • http://ponderosaclassof1990.com/clients/d/d5/d5d19f6fc184e1fdd834fc62be9f1763/File/rurepegisuriruwomo.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca14e9203d---luzekezi.pdfIn PDF document text
    • https://z87992961.com/upload/files/20210820012221.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/82ce8929413c70ba71608ac9fe1de071/kugexek.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/7593752122.pdfIn PDF document text
    • https://bakwanudang.com/contents//files/xitewemixatikotodozuro.pdfIn PDF document text
    • https://www.westcountrystoves.co.uk/wp-content/plugins/super-forms/uploads/php/files/be3645b10b8c83fe61fadcbf0cb504e5/16075572935.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16087ff5a9f220---joture.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/1qonpjdum6u0ea3aqop7mfv6j3/josorivot.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/nevalet.pdfIn PDF document text
    • http://business-plan-capalpha.eu/mbp/upload/images/images/upload/ckfinder/loporusimusexubimutori.pdfIn PDF document text
    • http://7tec.ru/userfiles/files/misideruzidag.pdfIn PDF document text
    • http://tw-tms.com/uploadpic/xw/files/29734506581.pdfIn PDF document text
    • https://o-dance.com/upload/files/nefudimobo.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/1d8f79729d998f2fb81a9aaddbba513d/16075209562.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/lukasiv.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/xuwetudigutofutuxap.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/xifodufunagufin.pdfIn PDF document text
    • http://xn--80aaae7amexjfdlfdfg.xn--p1ai/files/file/3112806261.pdfIn PDF document text
    • http://designpavelzapletal.cz/files/file/xikizifogarewewe.pdfIn PDF document text
    • http://pensacolahigh1964.com/clients/1/1d/1d652d7f5bd5fd2f3712913460b20393/File/80358981961.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=evaluating+functions+using+function+notation+worksheet+answersPDF 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_off0000c37b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC37B 10944 bytes
SHA-256: af796486379cc554ef60569c297261588efe21706da3a3c5d489b58ed257c5d4
font_01_sfnt_off0000dce2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f4f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4F4 17744 bytes
SHA-256: e013387b4393b28e56f9f0cd899cc1997a777b1cc5fbbf8229f062d0511ed9b7