Malicious PDF — malware analysis report

Static analysis result for SHA-256 2e399f37ac7d2f3a…

MALICIOUS

PDF

70.7 KB Created: 2021-09-25 17:01:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 509cb8f33f308ce6231129811c92bfc8 SHA-1: 1a448aaea2d49c58e43cdc94185283aea47e9830 SHA-256: 2e399f37ac7d2f3a21e8fa39af2bcf2afbaeff4fa5e867040793c7cb29f14db2
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple heuristics indicate it functions as a link farm, pointing to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware hosting sites. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

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://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1612f27b82e49c---putifawozuzivabaxepojuda.pdf
    • https://fishboat.hr/files/78707876586.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147d3054a798---binikukef.pdf
    • http://mundori.com/js/ckfinder/userfiles/files/3781449499.pdf
    • http://eg-connect.com/uploads/editorfiles/file///42368466804.pdf
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/jisalawafipuvikoduk.pdf
    • http://yourbuilding.ru/userfiles/files/vubewezolib.pdf
    • https://bangvetthuong.com/luutru/files/71640330616.pdf
    • http://lifebeachvilla.com/uploads/image/files/53042484760.pdf
    • http://www.sarajevo-inn-grunewald.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141183b4600a---dinofijuwuvoro.pdf
    • http://dreiseengrundschule.de/files/73143378060.pdf
    • http://z-i-f.ru/userfiles/file/24984612440.pdf
    • https://pasarantogel.com/contents/files/23515870640.pdf
    • http://yangpupark.com/uploadfile/files/7895908182.pdf
    • http://clubselectionvoyages.com/images/file/gikido.pdf
    • http://zhfangyuan.com/uploadfiles/files/seruderipe.pdf
    • http://jia-longsofa.com/uploadpic/jialong151126/files/202109020116069483.pdf
    • http://cameragiaminh.com/upload/files/munagifaposupega.pdf
    • http://pc-driver.ru/userfiles/files/wimofifixoxizapolosuzub.pdf
    • http://salamino.pl/userfiles/file/bufojepefavobilebiju.pdf
    • http://www.jindatunnel.com/up_files/file/xokirovu.pdf
    • http://barrospizzadb.com/uploads/files/56081169805.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=open+mobile+bookmarks+on+desktop+chrome
    • https://www.assessment.unibe.ch/app/webroot/js/ckfinder/userfiles/files/26329121344.pdf
    • http://elezioni2014.gds.it/userfiles/file/kepododalod.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • 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_off0000b53e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB53E 16792 bytes
font_01_sfnt_off0000cd50.bin
7d60b954a41b9912a5554bb10f984bdea78a8684b02f718bcfcc3dea534a27d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD50 16696 bytes
font_02_sfnt_off0000f7b3.bin
9329b2e3557ad3503fd104cdd88102dfbed913ae501dda155ff7047333bb9223
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B3 11036 bytes