Malicious PDF — malware analysis report

Static analysis result for SHA-256 3776c16262ef091e…

MALICIOUS

PDF

76.4 KB Created: 2021-09-01 09:30:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5c9df4bbeb8320df9fa4d51c68043308 SHA-1: 3f79bfbb9022684e729130b19fba55bd75a54d3d SHA-256: 3776c16262ef091e494c9f2ce5d1ed1ac937c8ab2eabe3c39916727d9849dea0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://crysiq.ru/uplcv?utm_term=assurant+direct+limited
    • http://dianacb.cz/userfiles/file/fatim.pdf
    • http://jfe.hk/userfiles/muwisuwemekunozofevok.pdf
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1d2d88853---memavuviwubudi.pdf
    • https://cape-electronics.com/media/file/xopopufugu.pdf
    • https://verandapattaya.com/userfiles/files/46942827594.pdf
    • http://primaria-ciocirlia.ro/media/file/juxiwesigamududolo.pdf
    • https://arnetbilgisayar.com/upload/ckfinder/files/nubovibixijowipagesaka.pdf
    • http://eschool365.in/js/admin/uploadfiles/file/2141965007.pdf
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/160878dae98cd4---4036637890.pdf
    • http://ohmamakitchen.com/uploads/files/61325377350.pdf
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/suzomonarofivowuxagover.pdf
    • http://vietthanhstone.com/images/news/file/14890120767.pdf
    • https://kawanmto.info/contents//files/54445143033.pdf
    • https://vettercycles.ch/userfiles/files/pegofoxotasatofisonelo.pdf
    • https://mygoaltv.com/ipp/images/uploads/files/miwimasiwotojafen.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/4a4f560e1a2fab6e288a27c470facb0e/wejilamesukifo.pdf
    • https://aadharshilaschool.org/userfiles/file/13189879746.pdf
    • http://chithanhplastics.com/uploads/userfiles/file/93661208214.pdf
    • http://scea.edu.mn/ckfinder/userfiles/files/limupinodaxudojafadasa.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9f5350d45a---tuwedererapokiguvifimepom.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d897ebd566---piturevisulorodajixegu.pdf
    • http://www.netcorp.hu/data/editorfile/gebonixabajera.pdf
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/f25a0cf87e41eb37623fcec1afc4c546/66047758239.pdf
    • http://teplo76.ru/uploads/file/zoludoludajut.pdf
    • https://xuantruongtech.com/images/ckeditor/files/rexeridutewetudo.pdf
    • http://akcjonariusz.com/UserFiles/file/paxezizapinopesiriz.pdf
    • 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_off0000c5ab.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5AB 16792 bytes
font_01_sfnt_off0000ddc2.bin
3d2774f36ae6d80b33ab8079c5ff8cb898c42b2322a5793f336b6f8435a31ac8
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC2 10492 bytes
font_02_sfnt_off0000f598.bin
96e3a5d472ee65e86f45dc7530f4a5ed984d34481415aa5ac0c1725b7cdd5dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF598 17852 bytes