Malicious PDF — malware analysis report

Static analysis result for SHA-256 9818598b4ed1ef3a…

MALICIOUS

PDF

75.2 KB Created: 2021-09-01 19:24:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c23847e880898427c1b2c39e967b9116 SHA-1: 20744c9c071a97041e30ef9a0d76b10f96f6be12 SHA-256: 9818598b4ed1ef3aadee205988f9b9dd97ff78a250216a243256c925ca40b845
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to obscure malicious destinations. The ML classifier also flagged this PDF as malicious with high confidence. No scripts were extracted, but the structure suggests a lure for users to click on these links, potentially leading to phishing or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9934

Heuristics 5

  • 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://vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/xomijopotoxoropobatezajox.pdf In PDF document text
    • https://arket.io/wp-content/plugins/super-forms/uploads/php/files/o76u4e5e7j1tkif2klco2hp6vo/2715775840.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610abb0139598---kerokugogumidopuvet.pdfIn PDF document text
    • https://anukulagrotech.com/userfiles/file/67599198217.pdfIn PDF document text
    • http://patrick-jardinage.fr/ckfinder/userfiles/files/lilaxo.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/354cc23b1c27e127149c7fe5d6c8f3b5/5357198680.pdfIn PDF document text
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/f15dd7677624fa845d0ff64bed3fa29b/79878546118.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/pd5djc0k18f601k38vp8l539gs/ridopefawodomimatagaviwig.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/zobolixirusidi.pdfIn PDF document text
    • http://knoxvillecentralhs1966.com/clients/8/8c/8c0a3a1fea337096d337135aeb812fb1/File/94659007147.pdfIn PDF document text
    • https://studyhalltracker.com/files/file/69000754893.pdfIn PDF document text
    • https://fuze-pay.com/ckfinder/userfiles/files/9589615177.pdfIn PDF document text
    • https://postelezmasivu-plzen.cz/ckfinder/userfiles/files/42158913397.pdfIn PDF document text
    • https://www.asahinadigital.com/wp-content/plugins/super-forms/uploads/php/files/kbh1ggkjgkpngl3gkjc6rjii16/69435264840.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16077f63910a7b---31553332903.pdfIn PDF document text
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/4723c52daf437ec635f5f479f8c5192f/83981353095.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/ruxigovirojuvop.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/73335682428.pdfIn PDF document text
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/bh72as0mqsrkekjtvob7in0ie9/dipimajiv.pdfIn PDF document text
    • http://cleanking.net/userData/board/file/40616955551.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/84764534055.pdfIn PDF document text
    • http://dodici12.ru/wp-content/plugins/super-forms/uploads/php/files/gnnm564g7ns0rr9v1n88rfijl6/manirukasedomalipotodelex.pdfIn PDF document text
    • http://www.wm-meyer.de/meyer/admin/editor/ckfinder/userfiles/files/94531753385.pdfIn PDF document text
    • https://e-ceramika.pl/userfiles/file/repotomuxejasafunobilesel.pdfIn PDF document text
    • https://medprobr.com.br/wp-content/plugins/super-forms/uploads/php/files/51f5ccea84161d8aa5626a0f20b6040a/11283751507.pdfIn PDF document text
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/43387270471.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=reason+for+ibsPDF link annotation
    • 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_off0000c632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC632 10248 bytes
SHA-256: b8fdd5be3c89a7ba061637aab2cac06addda625ff512f07ed9da37bad40b0505
font_01_sfnt_off0000dd53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD53 16176 bytes
SHA-256: e4f8e56cbfc87b03eec470caf1fb20c6bfc90125902e4c6eb13ebfc51dcc4986
font_02_sfnt_off00010678.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10678 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1