Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9eb48de74822ae8…

MALICIOUS

PDF

82.2 KB Created: 2021-09-06 20:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f9d87416ca362279fc6addf1a73d24ed SHA-1: 2d48981fa8ee61ac404abcc4dcea80c2b5e0dcf1 SHA-256: a9eb48de74822ae8775cdb135a1f6ae7de0f84037c6a7c6cbf2587d678046a2a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable domains. This behavior is indicative of a link farm, likely used for SEO manipulation or to distribute further malicious content. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://pistant.ru/uplcv?utm_term=flamenco+sketches+chords+pdf PDF link annotation
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5165082ec---gunimodujexo.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021043015030273499.pdfIn PDF document text
    • http://np-laser.com/upload_fck/file/2021-7-12/20210712211704637252.pdfIn PDF document text
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/4303gjp7s3l1fiudanh7bi9dm0/58060336039.pdfIn PDF document text
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbdb67b09e---86416184994.pdfIn PDF document text
    • https://shiphangnhanh.net/uploads/image/files/69265606193.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/16080a72f053a4---pamidemopesavif.pdfIn PDF document text
    • http://meuble-tunisie.com/userfiles/file/58275329365.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/sowafenelijuwulo.pdfIn PDF document text
    • http://yukamifashion.com/upload/files/70596097494.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/23355415335.pdfIn PDF document text
    • https://arch.ua/ckfinder/userfiles/files/ziwoxujafisesurorulud.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16090c6ff30415---zegokizeguganip.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/u6oov4qaal77o3nvsc3acea2iv/67250265679.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/basogusivujuwalevado.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/6020252519.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/3bef5708f65c511a4cb32e08e5f648b9/87291017100.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c23b833d96a---julataxiwojopil.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/7aafeb0ac2527dc2e11875206b330344/22577635808.pdfIn PDF document text
    • http://zulassungsservice4you.de/bilder/file/9235277839.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/71509361331.pdfIn PDF document text
    • http://evolutionchonburi.com/userfiles/files/ziredijilatu.pdfIn 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://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_off0000d685.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD685 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ee97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE97 20904 bytes
SHA-256: 0de21344d4d8851937f4aeb299aee302c09577d4579bdea3ecd6a2ffb0feb85d
font_02_sfnt_off000122aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122AA 10864 bytes
SHA-256: 796e33dc3408fa0dc606b76372f97aad7cbfe18dcf4dafed4fa909ae0910cbfb