Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3437cc88c44f984…

MALICIOUS

PDF

91.9 KB Created: 2021-06-28 17:56:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 939ca4d1313a4fc3af68ac431e08c1b8 SHA-1: 9c7f3a6a69ab8a3069398923333a09561a326f29 SHA-256: c3437cc88c44f98449ec5fb09237531d45c161f57379140a61c5d3d8d90d7e83
104 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 WordPress sites, suggesting an attempt to distribute malicious files. The ML classifier strongly indicated maliciousness, and heuristics identified it as a link farm on disposable hosting and potentially a download button lure. No scripts were extracted, but the structure and URL findings indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

Heuristics 6

  • 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://ccforum.kr/uploads/file/1621263119.pdf
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0dc12c500---vodel.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c306ba322e1---ruvitugosexilinipen.pdf
    • https://oncallanatomist.org/ckfinder/userfiles/files/75063966036.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3f96410d24---jatexidutobisoti.pdf
    • https://sharjahcements.com/images/bulk_images/files/23152704212.pdf
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/j7q0f8mgv8kn7v3nn379ncnnvr/5615969659.pdf
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6ea004586---gazotakufujazoroseta.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc71d2f1ab---rufefamo.pdf
    • http://stsaischoolamritsar.com/slbdavbatala/userfiles/file/40666987700.pdf
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/678b3be3df7a647d6e94290f40efb94a/paxekobagetudaxa.pdf
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c7360733fad---69239721536.pdf
    • http://geology.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1608e98fdbf39a---kedufamerexitaxefelo.pdf
    • http://chono.mn/uploads/userfiles/files/93129074596.pdf
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/b84aa5f290b4398873dd7e833e8eaf33/68320379272.pdf
    • https://samngaimarble.com/html_upload/file/30667320341.pdf
    • https://alatheir.com/atheirwsfiles/file/kesogozanulotepivawupabon.pdf
    • http://simonide.org/userfiles/file/vupapifusofeloximivojosa.pdf
    • http://bonsaichik.ru/images_uploads/files/jijat.pdf
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/64e0a3cdd086ff844503a7599124468d/nukuwemilijinuvoxoze.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085d98001e59---52098011924.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/bfb89e53f77bf41654b0f062959ba589/66219147468.pdf
    • http://uralinteh.com/uploads/files/nosibopizajivusoledowed.pdf
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/4d0c4d3f350d9544a2e8ceae40fd5791/sivolezaruputu.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=corporate+presentation+ppt+templates
    • 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_off00010630.bin
f3fa609915b3295180b99df4034eb08b3aa5249d0d2033affe706d378576c68e
pdf-font-stream PDF embedded font (sfnt) at offset 0x10630 10444 bytes
font_01_sfnt_off00011dde.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DDE 16792 bytes
font_02_sfnt_off000135f0.bin
e260889fdbb6d2af82d1c57ecee49a54867d8d6a7de0cea285f1eb4025c7e8be
pdf-font-stream PDF embedded font (sfnt) at offset 0x135F0 17292 bytes