Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1692f8e2efbe8e…

MALICIOUS

PDF

91.0 KB Created: 2021-07-03 13:01:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 91aaaaae63f2ffe94dc7d2915c3ffae8 SHA-1: a2790527c4c2dda3fb5266b66d1c53b92239b335 SHA-256: 8c1692f8e2efbe8e093e57198140b7fca28267061b026f59ea7ff84e20de8477
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded links, many pointing to compromised WordPress upload directories, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were directly extracted, the presence of external links and the nature of the heuristics point towards a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://misosmile.com/upload/editor/files/29404314493.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4f8437c85f---6181564434.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/98cd086b8890bd82abcfc5f7b670d1de/60162564089.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/a0b2c05536cd998f704f3cd42ab53a2f/sifakuregirudumenid.pdf
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c966ed0ea32---6974158183.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/c62981dd3ee9fc94481c866edae20887/98112489117.pdf
    • http://huron81reunion.com/clients/f/fe/feec28e48c841af8be4ad6373737a022/File/gurolererizofepewoduru.pdf
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/731m39do3j9rh5q68inbp0ulc1/zefixeworegotarapomoze.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160df3d7e4922f---66880329345.pdf
    • https://alllegaltask.com/wp-content/plugins/super-forms/uploads/php/files/jcpgmgeqqgrd7jh3vesh6mshk4/37572421595.pdf
    • http://talk200.com/admin/admin/uploadfiles/file/lifakun.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f2cf42728e---82547335226.pdf
    • http://vtvxm.vn/userfiles/file/3894808131.pdf
    • http://www.petercar0937494634.com/upload/img/files/kuzunevogonerirutajikawuk.pdf
    • http://www.pranabkumar.com/fckimages/file/lexuremisewodubepuvow.pdf
    • https://culturasiapamplona.com/guiarte_userfiles/files/34530240392.pdf
    • https://tanthuantelecom.com/upload/fck/file/jetexujuxarerexupawoxupuf.pdf
    • http://asianmosaicnyc.com/userfiles/file/31847327028.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609eaa71ace4e---walimolomidumuju.pdf
    • http://fitviewer.de/files/file/38939438228.pdf
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/r10o132s67tv6eqdimhot5do52/52772349378.pdf
    • https://abe-rdc.com/userfiles/file/59601750940.pdf
    • http://artistalexanderkanevskyroyalshakespeareglobetheatrelondon.com/clientMedia/file/fuxilurevivegozu.pdf
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/0d143e963906dc50d3a75d752902b158/94640407241.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=schizophrenic+tendencies+meaning
    • 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_off00010181.bin
93131d6d061d2a6ddc3faa0b0704cfbf4ea77ae2af8db3a93a8421307057bded
pdf-font-stream PDF embedded font (sfnt) at offset 0x10181 16828 bytes
font_01_sfnt_off00012d1e.bin
1c8536cf7fc4d5969e2bb79a6f39035c89a62e71d535363649c507ce0bec13cf
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D1E 11052 bytes
font_02_sfnt_off00014681.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14681 16792 bytes