Malicious PDF — malware analysis report

Static analysis result for SHA-256 539b026a7d9a703e…

MALICIOUS

PDF

84.3 KB Created: 2021-06-20 13:59:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 9f9f3fbb58294365a017f99b5201a7c4 SHA-1: ef7500a585d1cf281c95779414908881f24a30ec SHA-256: 539b026a7d9a703e85d978b5f42add8fc178be9322eceaa9f26aedaaaa6cb951
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://coretry.ru/uplcv?utm_term=o+comunista+exposto+pdf PDF link annotation
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160b927788ccd9---vupafebipigav.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/adtukirdr5rkdikvepsa5k8839/mesajonaxuwibugarosu.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/ba37e5842706dd7eeeaed4c9936baaed/42852533521.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/csljg93var104856e1usrpplvo/13042639401.pdfIn PDF document text
    • http://sns-russia.ru/userfiles/file/43206744996.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/53b85ddeb178a97078b12f075130a9db/tuvil.pdfIn PDF document text
    • http://93564497.com/userfiles/11242971312.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160ca368a497ad---82637465741.pdfIn PDF document text
    • http://ahchala.com/img/file/zumidinigogigu.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/4293620794.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/a8c0d75e7572920dc218912817dd0777/9129392449.pdfIn PDF document text
    • https://fenixfalt.com/userfiles/file/50532483367.pdfIn PDF document text
    • http://westleyden72reunion.com/clients/4/46/469dc9162705cbff2d1fbe132f144f37/File/54898594026.pdfIn PDF document text
    • http://weilandensemble.nl/ckfinder/userfiles/files/98975639572.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bcb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCB4 13028 bytes
SHA-256: cc3eaa91d4b04fcd97f063c9fbd44619eda81df01601ccfd3f6f6939f4abfe7f
font_01_sfnt_off0000e6cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CF 5148 bytes
SHA-256: 95da46345896d180f1f5e215bba0b32c9e8368f35a685bafff44b23f85ad95dd
font_02_sfnt_off0000f840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF840 12244 bytes
SHA-256: 6939a7a32e018645e046d3b0d72a5885696dfd40a5f3d139515636f225874171
font_03_sfnt_off00011e58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E58 16284 bytes
SHA-256: 7d4c99e5848b82ae0f3ef793c73c312d39ab9f816e7a737d6af528da91cdd53f
font_04_sfnt_off000133ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133EE 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378