Malicious PDF — malware analysis report

Static analysis result for SHA-256 4592b4bd9e36ce18…

MALICIOUS

PDF

94.8 KB Created: 2021-07-03 11:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c55ae19a43ebd53981d0029458320909 SHA-1: cc91ec7626098cddfa89f89e127b04405c935bcf SHA-256: 4592b4bd9e36ce1812c0f37bddc5095248b04d91316a3d93d185b9361c99ccea
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm pointing to various PDF files hosted on potentially compromised websites, suggesting a phishing or malware distribution campaign. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://e-sportis.com/images/upload/489308522.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-6-12/20210612171322823775.pdf
    • http://www.aportecnica.com/imagenes/editor/file/47170289389.pdf
    • http://montaze.org/democms/userfiles/file/41593029823.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c9392e2888---senadomubokivibap.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16099d76296bc9---kazowasazopelenom.pdf
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/272bf32c5f7a1923d06eaaba7280b9b9/81513258134.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bb29b522ff2---zimagobokij.pdf
    • http://shinies.ru/img/lib/file/sodugojezelex.pdf
    • http://veraschwemmle.de/fckdata/file/wakakekirivoxudigibuniboj.pdf
    • http://essiac.cz/UserFiles/file/sibepazaz.pdf
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160d01e6e5b41e---memizipiwowogeguluri.pdf
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/totv39qnsm4kivmfgefqhf5bu3/52298302234.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea3345b5b9---5365531229.pdf
    • http://saovietgroup.com/upload/FCK/file/30110101012.pdf
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/vavikorodozavol.pdf
    • http://veronicanealhome.com/wp-content/plugins/formcraft/file-upload/server/content/files/2/1609455399d7b9---sugepijorivitaka.pdf
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16072a94d4d6bc---44304143728.pdf
    • http://canevinclassof70.com/clients/6/6b/6b8b8ee0d314e59372afbcb75100d768/File/71646323156.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082faa787466---gobatepufebewibadot.pdf
    • http://mikomisushiwc.com/uploads/files/wiliwabemewamamopivap.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e3dedc506---55086260595.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/983d5ffd19bff2317bb9cae722c48ee9/kokedimumalobuje.pdf
    • https://promobryansk.ru/userfiles/files/wunatasuvoxudap.pdf
    • http://afgventuregroup.com/cfiles/file/92980949246.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=contraceptive+methods+for+women
    • 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_off00010f0d.bin
12af5055d6461d85b16daf53a82f4cb9bb11c3cf24a625d258e27309e0597508
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0D 11020 bytes
font_01_sfnt_off00012897.bin
00852ff7d07c4917c0d99f103e1bd5a8f3fa8a07d14cfd69472c4cb21526c4ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x12897 17284 bytes
font_02_sfnt_off000155bf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x155BF 16792 bytes