Malicious PDF — malware analysis report

Static analysis result for SHA-256 a351c82f1f3a7a9d…

MALICIOUS

PDF

87.5 KB Created: 2021-06-28 23:09:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 27170f6fd2277a017a45a9467a1672a4 SHA-1: d308456113440618072317e63adeb6410e4434f3 SHA-256: a351c82f1f3a7a9d817ebc56a55b406a1859f31ae0a582d15bf4636cd55c788c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised CMS upload storage, suggesting a phishing or redirection scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites or download further payloads. No scripts were extracted, but the structure and URL findings are sufficient to classify this as a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://drafthe.ru/uplcv?utm_term=introducing+pullets+to+hens
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/11ld439tdijjof6mmrt3o37se3/vezoritom.pdf
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/21792793353.pdf
    • http://didocrosby.com/imagenes/file/59783701708.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/4l94vca7osquo454mq1fa3a5l5/21500999223.pdf
    • https://propiedades.net/ckfinder/userfiles/files/77896090724.pdf
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c951f5ea11---58954372136.pdf
    • https://ryokanclub.com/FileData/ckfinder/files/20210627_ED754D89C92A09B1.pdf
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ba15ec279e1---10882973180.pdf
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e608f4dc49---paluvefizoselupugito.pdf
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfc722a5b41---52873097469.pdf
    • http://dioceseofniranam.org/userfiles/file/59011455105.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086a60b1954f---31855159556.pdf
    • https://nothingbutsafetyglasses.com/userfiles/file/dikumanofoke.pdf
    • http://lnshiyue.com/userfiles/file/20210603005012_1739698029.pdf
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/0j5md8tocbiahr0o3ccc61gfb5/nitinenaxozixaxuw.pdf
    • http://grupophi.es/uploads/files/83853722049.pdf
    • http://sistersaviopublicschool.com/userfiles/file/vubipipawu.pdf
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3b0501425e---9406494638.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608082422fd43---26389540441.pdf
    • http://asianmosaicnyc.com/userfiles/file/tudifupagaka.pdf
    • http://jfkanacon.org/data/userfiles/files/25745899197.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/722eb901fa0d00e95b03de9d080fbea1/73479117103.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/145ebe75078aa9b8a7f9b58374e3d9a7/96204916570.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3c0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C0 16792 bytes
font_01_sfnt_off00010bd7.bin
8678b471843bec337cd4dc3725a1eecef8e71eb88657bd7b664f51b5fcc8bbaa
pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD7 10680 bytes
font_02_sfnt_off00012403.bin
5c832d8a494603da2a71ac5904eaba25d1440f739bda2e644f37aee78ec6e371
pdf-font-stream PDF embedded font (sfnt) at offset 0x12403 17220 bytes