Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9538165be25f1b1…

MALICIOUS

PDF

75.2 KB Created: 2021-09-16 18:09:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 81583dda308d03d11e80894507b9de94 SHA-1: 5f08d6bc7b59661afca73c271bab6854c75f3985 SHA-256: b9538165be25f1b1d34054734ae0d9add92cb19fbbe9d0d730c2b145924088f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. One prominent URL, 'https://oniceh.ru/uplcv?utm_term=gta+5+1.52+free+download', indicates a lure to download a game, likely a pretext for delivering malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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.
  • 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://oniceh.ru/uplcv?utm_term=gta+5+1.52+free+download PDF link annotation
    • http://tythb.com/uploadfile/files/sezimepiviloziwidatelifi.pdfIn PDF document text
    • http://bensonlandscape.com/editorData/file/taridolagigituletuku.pdfIn PDF document text
    • https://xn----7sbeo1acdy3adh.xn--p1ai/userfiles/file/bakixitor.pdfIn PDF document text
    • https://path.mn/userfiles/files/56440725660.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/lemesegosupodud.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161388e96e04fc---jimexosodureti.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/cfdea979e51cba14672c527b45e630d6/57245805368.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/52190561334.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b64b17431---3795377224.pdfIn PDF document text
    • http://bargiel.com.pl/ckfinder/userfiles/files/jowaserajufoz.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/wodomirukogepojevetize.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/kubodadobubux.pdfIn PDF document text
    • https://ingatlanfelugyelet.hu/uploads/file/kudirevevo.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/ruwukujixesoxal.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109100910507246.pdfIn PDF document text
    • http://computergramm.com/userfiles/file/mabiduzaku.pdfIn PDF document text
    • https://es21sys.com/userfiles/file/wazufu.pdfIn PDF document text
    • https://juraganmonyet.com/contents/files/27542738548.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/64004738999.pdfIn PDF document text
    • https://zd-zeta.com/uploads/files/202109151157241289.pdfIn PDF document text
    • http://tuvanthanhlapcongty.biz/upload/ck/files/78444301831.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/88915510319.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/37648046868.pdfIn PDF document text
    • 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_off0000bf37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF37 18308 bytes
SHA-256: 3a844b5dd29d70f55bb03ccf24a419945208036a77e2ec3cd05e114a7fbfce38
font_01_sfnt_off0000ef56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF56 10584 bytes
SHA-256: b8a013e98709063be47c7c27500d2292a946e8e90cd19e21e0021ff214e21e16
font_02_sfnt_off000107e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1