Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd92db31dfe8e2e5…

MALICIOUS

PDF

74.4 KB Created: 2021-09-16 20:29:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: bfc6d0de17df7b3e01b2556f7b3f8ba3 SHA-1: 8cd9d51b710956d9d26689ecb73996b0e3ac53b9 SHA-256: cd92db31dfe8e2e52b8d65623c1b016638a97923d0a04dd0c9f9b2ce2f83b825
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to compromised WordPress sites or disposable domains, indicating a link farm designed to lead users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and link farm nature are indicative of techniques used to exploit vulnerabilities or trick users into downloading further payloads.

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 https://chcial.ru/uplcv?utm_term=hack+walking+dead+road+to+survival PDF link annotation
    • http://dreamsurgerycn.com/ckupload/files/nanuvojeza.pdfIn PDF document text
    • https://arerp.kr/data/file///39849718904.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/39553051509.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/4b68af058932164dff8a10689e810f61/84444138796.pdfIn PDF document text
    • http://e68momo.com/shopadmin/upload/files/gowikilow.pdfIn PDF document text
    • http://abpaluso.com/upload/file/mubevitapud.pdfIn PDF document text
    • https://latgalesamatnieki.lv/files/file/88736205039.pdfIn PDF document text
    • https://fallahi-sch.com/userfiles/file/rolinilaxewimuzuxilunut.pdfIn PDF document text
    • http://www.sospapa24.com/lib/ckfinder/imgupload/files/80567699471.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1630955738.pdfIn PDF document text
    • https://armenia4d.com/contents/files/16976826908.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/10806280478.pdfIn PDF document text
    • http://eca.or.th/ckfinder/userfiles/files/51498453216.pdfIn PDF document text
    • https://ski-valloire.com/ckfinder/userfiles/files/fupasarijegerebajuzebikis.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/93028390ec2d89561f5c1b3f108b79aa/tevawulejajavado.pdfIn PDF document text
    • http://scandirent-new.ru/uploads/assets/file/fufawimu.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/23e662ff0369f082e9cd1f7ec6306cf0/68446060496.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/zapatibunijuxojitujupopox.pdfIn PDF document text
    • https://wupaojichangjia.com/d/files/topunudugu.pdfIn PDF document text
    • http://3gr-group-com.gbintl.com/ci/userfiles/files/14486691742.pdfIn PDF document text
    • http://kfbma.org/files/fck/file/65820366055.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/toxesokoxeraxa.pdfIn PDF document text
    • http://csc028.com/userfiles/file/20210906041938_khcogr.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_off0000c0a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BB 10880 bytes
SHA-256: b54c131ad37a5aaeb7b5d4a72ebdb272f4baa99f6d903947b551ec3f81423a85
font_02_sfnt_off0000f1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DA 16164 bytes
SHA-256: dd417d48aabeb7740423649147cbcfd06afc5d139251f33c77baa7d8e84cb1a1