Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4970b7c1bfda335…

MALICIOUS

PDF

79.8 KB Created: 2021-06-21 01:43:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 0d7bf1dd0fd68730ae77ef165d1ae173 SHA-1: af722ac843c092931fd872cc053b533979777e0d SHA-256: c4970b7c1bfda33556431eb9528e74a4b81dafe7e7fc0b7932cb293bb31140e3
96 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by 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 0.9998

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://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b3d8fb4fb13---27921745618.pdf In PDF document text
    • http://surtek.biz/image/files/20150128_020502.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffd0b682e2---datimusijaxoxo.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d074a59fea---binevazezejorovines.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16085259b9482c---50093034498.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/84672856409.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/cior6ldjf8r9qgrh707qheln6s/juferaganujevew.pdfIn PDF document text
    • http://ankurgroups.com/userfiles/file/povelevimoxuxupukevuxasej.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/87913519899.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609934c48c94d---talok.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2aaf8b1522---45562308324.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a7144cbfb9---61380712840.pdfIn PDF document text
    • https://seerupit.dk/assens/file/42564219281.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b433ac8bc39---kiwugunijaxuvaradafitug.pdfIn PDF document text
    • https://cwlighting.com/wp-content/plugins/super-forms/uploads/php/files/37ff178d80b216da4763ca10ac1cb8e1/sopaloxerikewudusukepak.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4acbad1ce8---virilanukaduwunusuto.pdfIn PDF document text
    • http://auapp.ch/userfiles/files/sugumanirarowegefogalagus.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/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=minigore+2+mod+apkPDF 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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00011450.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x11450 18700 bytes
SHA-256: 28ac7ae4239401f30f8d86c8ff23e8e8d065b65fa53b8b04bf9611e34409ca2b
font_00_sfnt_off0000d86c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD86C 5272 bytes
SHA-256: 9f4bf195792a1870101a9d936e976988a6e1ef6b4c866ccebdab81dc98960cc9
font_01_sfnt_off0000ea52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA52 13872 bytes
SHA-256: d75c7e8f920df6096ef435c1974a199993dc94976971c6535617ececbbf8c1c1