Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d3fdbb9996f044c…

MALICIOUS

PDF

75.1 KB Created: 2021-09-14 23:42:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b9cf5dee14690bf9cecb46f867220fe3 SHA-1: 58ce7b802ee57d18034bfc157b2cd45954602a88 SHA-256: 1d3fdbb9996f044c54b0aafff7b644704378459bf45791038a7ae707f43b635c
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to various URLs, some of which are hosted on compromised CMS uploads, suggesting an attempt to obscure the final malicious destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://conviviodihera.it/dati/upload/file/jilokupivavesog.pdf
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/59619853511.pdf
    • https://zibarajabi.com/cache/fck_files/file/gowurojasimoruzozep.pdf
    • http://changwontour.kr/FileData/ckfinder/files/20210909_42EF589357137A5C.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/59564693212.pdf
    • http://vejwun.cz/images/ramosezu.pdf
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/161353ce85205f---23999909228.pdf
    • https://www.colegiodomus.com.br/js/ckfinder/userfiles/files/91204011535.pdf
    • http://yonseri.org/userfiles/files/nelubelutubeda.pdf
    • https://marbeyoyun.com/calisma2/files/uploads/67313561717.pdf
    • https://muzpony.de/obrazki/file/90380147103.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe9aa06cb2---32844979592.pdf
    • https://onderhoudnlgarantie.nl/upload/file/barigogebake.pdf
    • https://ustunbilgisayar.com/userfiles/files/90922236389.pdf
    • http://speednewslive24.com/assets/ckfinder/core/connector/php/uploads/files/vixinugebemovudar.pdf
    • http://moscreen.in/cmsfiles/file/37734012219.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b69932a62---dapujigexurefi.pdf
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles/files/xometupuwexovu.pdf
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/41190466784.pdf
    • https://gencshoworganizasyon.com/upload/ckfinder/files/janifawevuduw.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/161304b8ed46e5---lejelowixililojagur.pdf
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/90058471361360113579f0.pdf
    • http://ksiclub.org/projects/achievemore/admin/upload/fckImages/file/xuxigigipudijudigigunig.pdf
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/91005476610.pdf
    • https://sarvodayasamaj.uk/upload/files/powonokogaw.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=unlimited+koin+higgs+domino
    • 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_off0000c200.bin
22b76ea7d05b52a3b7f655ed6a625db261b513c67ffa96bf0f09b1ca490f57e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xC200 16972 bytes
font_01_sfnt_off0000eddb.bin
0720f04f6e50ee9464ec473087b7aab0611bba774c83ddcd26899e0da9cd29e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDB 10532 bytes
font_02_sfnt_off00010562.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10562 16792 bytes