Malicious PDF — malware analysis report

Static analysis result for SHA-256 b78e6608c211b2d5…

MALICIOUS

PDF

77.5 KB Created: 2021-09-08 11:53:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c2a2fb13980179dc226dc75254b9a46f SHA-1: 585e92eab7ea68de443e6dce870990daccd4d454 SHA-256: b78e6608c211b2d5d2662aa5f53063fdadac05da078f8c051ab26d8a98a75062
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites hosting other PDF files, indicating a link farm designed to distribute malicious content. ClamAV detected this as Pdf.Phishing.Trojan, and ML classifiers also flagged it as malicious. The document's structure and the nature of the embedded URLs strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607862fae14de---89574530676.pdf In PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/16097ad12685d6---zevozimuputikewojirefa.pdfIn PDF document text
    • http://xn--knstlerische-biografie-arbeit-lbd.ch/userfiles/files/83800334522.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607953306a31b---9845204623.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608f74dba5b45---zuraboroxujinunuxezalas.pdfIn PDF document text
    • https://almuhja.net/ckfinder/userfiles/files/35665983899.pdfIn PDF document text
    • http://ilkjv.com/Images/Media/files/24705976420.pdfIn PDF document text
    • http://newworldss.com/uploads/file/15457486878.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160813068667f8---12844463587.pdfIn PDF document text
    • http://ktcz.eu/files/files/55850563296.pdfIn PDF document text
    • http://xn----7sbev0bhje.xn--p1ai/images/news/file/duzomir.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16089005db1354---rupejutema.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/9a853002ff9c561bb5babe3785bad6e3/60757070531.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160b28e51d2a6f---2095609597.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/f64ac1acd813d3e1b8c882553a103b5b/16614376513.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/2sp9b0cvo401j9oeoc3elacoh7/2446645811.pdfIn PDF document text
    • http://rosewoodcity.org/nbloom/fckuploads/file/ruwifabaguxutedexevekesu.pdfIn PDF document text
    • https://knurussian.kr/DATA/upload/files/202108161436185318.pdfIn PDF document text
    • https://lrdreamteam.com/files/files/file/InfoProduct/file/dosog.pdfIn PDF document text
    • https://thepainter.asia/upload/files/51024034930.pdfIn PDF document text
    • http://centronegozi.com/public/18450349862.pdfIn PDF document text
    • http://jfhcoaching.com/userfiles/files/9142502099.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/kijam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=london+map+with+tube+stations+pdfPDF 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_off0000c8f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F9 10900 bytes
SHA-256: b4f9ccb2a1f6bb210f812f74b06f656ed6ccf713dc18922f8def0e19990d86ea
font_01_sfnt_off0000e1d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D1 18100 bytes
SHA-256: c64b48741dfb5e342bc8f7a1b34e2c9992f7d3b78c858c2d69dff81e5c3e828d
font_02_sfnt_off00011064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11064 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1