Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3b6c5a804ee940…

MALICIOUS

PDF

68.4 KB Created: 2021-09-25 01:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 34e7480fce0541191864fcc8890231d1 SHA-1: 82e2d5b17c4e36acc3d84393b98e2cee1c18527a SHA-256: ac3b6c5a804ee94097819ced9e94bf7bb1b42032797f1c170e347e695c7fea19
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple external URIs and link farm heuristics supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://oniceh.ru/uplcv?utm_term=how+to+stop+auto+refresh+in+chrome+android PDF link annotation
    • http://mwflower.com/upimagesfile///sutojunutavazozokopopa.pdfIn PDF document text
    • http://profitoolinfo.ru/ckfinder/userfiles/files/69389465362.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/17785429525.pdfIn PDF document text
    • http://xn--2e0b30g3uq7pay7m.com/upload/fckeditor/file/6339664122.pdfIn PDF document text
    • http://hanleyresources.com/images/44920175585.pdfIn PDF document text
    • http://thechitay.com/uploads/userfiles/file/jazakuwoje.pdfIn PDF document text
    • http://izhar-energy.com/userfiles/file/rubujelibasujejamapu.pdfIn PDF document text
    • http://ageddfjtjgrade.pretty-match.com/upload/files/vovidujexuzekutajej.pdfIn PDF document text
    • http://hacoauto.vn/upload/files/munepebipilokilopeguki.pdfIn PDF document text
    • http://jia-longsofa.com/uploadpic/jialong151126/files/202109190251003776.pdfIn PDF document text
    • http://aexpress.lv/index/images/up/file/66986987813.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.com/upload/files/51530602255.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ddf96ac8f---zazaluxagewaxunimopugi.pdfIn PDF document text
    • https://etadelloro.it/images/file/44152454725.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/91518418590.pdfIn PDF document text
    • https://imaggu.com/ci/userfiles/files/3337104574.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16140063844bdc---6493304513.pdfIn PDF document text
    • http://www.insight-assessment.com/ckfinder/userfiles/files/21634873536.pdfIn PDF document text
    • http://aumnat2car.com/ckfinder/core/connector/php/upload/files/korufodelajiruvopitafudo.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/47473776461.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/45561897986.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161469a747c024---nuneno.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/vezukudulawes.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_off0000ae72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE72 14536 bytes
SHA-256: 461093300c89a6b789c78178551821cd624fab2e8b44e0ef463243dc4e6e3377
font_01_sfnt_off0000d2b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2B0 11016 bytes
SHA-256: 281d8d8d13e849a505df45cc33fce627f14668dd265582b8f028fd65350e8ae0
font_02_sfnt_off0000ec2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC2B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1