Malicious PDF — malware analysis report

Static analysis result for SHA-256 670582c592e0ee96…

MALICIOUS

PDF

83.3 KB Created: 2021-09-18 20:15:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dc603db53c68147e869b561a53a233c2 SHA-1: 4c861968f6909002cb69781b363867dae98c783b SHA-256: 670582c592e0ee96e03e49f84f21f755898f2191c724fd8d24a19bbb3fe07101
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised CMS upload locations, suggesting an attempt to distribute malicious files or redirect users to phishing sites. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body is heavily obfuscated and unreadable, providing no direct clues about the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135bd423819f---mitati.pdf
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/60473799016.pdf
    • https://cancelaria.pl/galeria/file/tewujofesepabepijazisaro.pdf
    • https://stichtingech.org/ckfinder/userfiles/files/14747354052.pdf
    • https://cornwallstaffagency.com/userfiles/file/liwibo.pdf
    • https://5udua.com/contents/files/6948724674.pdf
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/fivufugi.pdf
    • http://capesociety.ca/uploads/files/66169768248.pdf
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/bukiwumemisati.pdf
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1e8c9c137---fedusofoluxijodidaveloko.pdf
    • https://muachungbaohiem.com/uploads/userfiles/file/tikaje.pdf
    • http://miyagi.chi-kara.net/Upload/files/4966951351.pdf
    • https://kapokcmassage.com/uploads/files/202109100615236604.pdf
    • http://kleinschadenexpert.de/userfiles/file/9614415324.pdf
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/76999757182.pdf
    • http://kuryakyn.ru/userfiles/file/60211530062.pdf
    • http://fujiya-burbank.com/uploads/files/nepebitanasuj.pdf
    • http://saddabro.com/userfiles/file/83645729150.pdf
    • https://keyseries.us/userfiles/file/14208013220.pdf
    • https://chatham-ebenezer.ckdomain.com/uploads/userfiles/files/voxuju.pdf
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/1613b04b8ebd5e---mepipusujufifonetabu.pdf
    • http://96stone.ru/userfiles/file/gejaru.pdf
    • http://novichiha.ru/pic/file/62132927803.pdf
    • http://car-zone.sk/data/data/file/wafunuzawuretuwibona.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=iphone+x+vs+note+20
    • 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_off0000ddc3.bin
5cb26b00d201198232d3e01e3e6d2cd5aeedef5f534e0d1cd3d45f9ff28cd310
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC3 19504 bytes
font_01_sfnt_off00011057.bin
c6a8918f2a7e5feeb4e0b1ad8b307c9f7200271b34b20247b0259277b7a956e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x11057 10312 bytes
font_02_sfnt_off0001279d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1279D 16792 bytes