Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca816d38de022e34…

MALICIOUS

PDF

86.0 KB Created: 2021-06-27 21:37:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c6e1a44cc54632d603473afdd84c4e40 SHA-1: cfcfba3d4a3d4ffb9383aceb804be49ff8b00093 SHA-256: ca816d38de022e342e5de17b5f675cad634d8a0ae1e1fa06423f804a26a1fef8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious document techniques.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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://oio.cn/uploadfiles/files/22600856782.pdf
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/b122d715c58f166e3434771bdbb1d5b9/butejapofibubota.pdf
    • http://www.chicagoalphas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160791f864ec04---tukajogakikidimomevuvilut.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160996ca609bb9---joxovarapag.pdf
    • http://igigeothermal.jp/userfiles/file/xekojerunuzol.pdf
    • https://flycam.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609d23ceae4d1---19333834242.pdf
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/373a4da9dff19ed2fc4b4e967ed1a126/93747626488.pdf
    • http://michaelwilliamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/99885292475.pdf
    • http://air-ned.com/uploads/files/minemepelinope.pdf
    • https://www.prestigeautobody.com.au/wp-content/plugins/super-forms/uploads/php/files/627053ad4aa6d93d3851dda7e579e8e0/7021852283.pdf
    • https://medprobr.com.br/wp-content/plugins/super-forms/uploads/php/files/0af6528b093de91dd2bacd306b897de9/96985062600.pdf
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/d9ffecb22eb3175f76ad7ed32834e229/sarono.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/maldma7omk2osc8uv9im0v1ju7/wewejenifa.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1606d56bc36992---jotupedavowogoj.pdf
    • https://cualuoihoanmy.com/uploads/userfiles/file/56903826251.pdf
    • https://oddluzanie.net/userfiles/file/forazigat.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/998f3cdf1d8959e9047b65858334e069/gudadakidigam.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfe7801a00c---pezipararakoxewe.pdf
    • http://homeopathyhongkong.cn/files/45121497750.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/7ba83238b6a514ba1aa25877dc83a4fe/95427014759.pdf
    • http://resetimpianti.it/reset/public/file/38486469614.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=about+environment+day
    • 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_off0000edff.bin
c7c2cb8a92289fa20c2d96c6a6f536e3369332d077910ae48f7049df1ea65b6d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDFF 17120 bytes
font_01_sfnt_off00011ab7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11AB7 16792 bytes
font_02_sfnt_off000132ce.bin
1e71c567d620c56a953a3372de21d72876c0668fedc8b92337f6db73d887dd23
pdf-font-stream PDF embedded font (sfnt) at offset 0x132CE 10596 bytes