Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd0586f7a19a9317…

MALICIOUS

PDF

87.4 KB Created: 2021-09-04 14:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4e939903cd8a7224d3ef9b3bd7316d37 SHA-1: 0f5b39a1d27676f3c42c366d6eab168c2cf8b6d8 SHA-256: bd0586f7a19a9317e06cc481cdb93d0a40f85d6fc8c09482534f4860e9d3a0e4
164 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, hosting numerous PDF files on compromised CMS upload directories, likely to deceive users into downloading further payloads. The presence of a 'download button' lure further supports this phishing-like attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b06c45a316d---jidozipezesikuwevubop.pdf
    • http://koryosushi.com/uploads/files/57177306581.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160957d8b21768---lilazexarubu.pdf
    • http://evohome.pl/userfiles/file/83731145461.pdf
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/84301189365.pdf
    • http://montazenabytkupraha.cz/files/file/35930453044.pdf
    • http://foto-klub.dk/userfiles/file/doretasemurow.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/0a7mr9bjdf6uct9e02u1rlb702/wexefivubi.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddfef81b64---85698682930.pdf
    • https://allcreaturesinc.com/files/files/tidadu.pdf
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/43444209922.pdf
    • http://premsaktidal.in/userfiles/file/59154263384.pdf
    • https://evermoral.hk/upload/file/1626556872.pdf
    • http://kvbm.org/pds/userfiles/files/tuwifavevutojaf.pdf
    • http://fsanaq.com/upload/file/210706110728664002rxet7blok0ep.pdf
    • http://agataklimowska.pl/userfiles/file/17091048532.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f89ff59bd4---8030055179.pdf
    • https://infiniteprospects.com/FCKeditor/file/monepiwobodelujoxelabafi.pdf
    • http://erdivigado.hu/userkepek/file/24053559783.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/990d339b54c0af90345fbc9042625fac/magufer.pdf
    • http://redigonda.it/userfiles/files/jizori.pdf
    • http://immobilieninvestors.eu/userfiles/file/64547556332.pdf
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/b9a49cfa0f8f1277145aabb0230c54c1/55234415420.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=compress+pdf+in+adobe+acrobat+reader
    • 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_off0000f274.bin
02f5217837e938142ccf63b225ad8430e1a4948aac1213c655936bf4e927c102
pdf-font-stream PDF embedded font (sfnt) at offset 0xF274 10904 bytes
font_01_sfnt_off00010b77.bin
f19e55791d2d3af1b12305bbfdc3d863aa45479cbeb6861ea64d60eb39238da9
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B77 17548 bytes
font_02_sfnt_off0001384b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1384B 16792 bytes