Malicious PDF — malware analysis report

Static analysis result for SHA-256 8837858210bfdf8a…

MALICIOUS

PDF

92.0 KB Created: 2021-07-13 07:07:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0b3d2612218831a085e848fb09fade76 SHA-1: c851d9a23a74c34350f5943479ff6aa276af27c8 SHA-256: 8837858210bfdf8a7c0cb8267ffc61aeab7c6e8175f401c93236a150de0e3281
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDFs hosted on various domains, many of which appear to be compromised or disposable. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the structure and URL patterns suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://kxnjl.com/userfiles/files/37710699875.pdf In PDF document text
    • http://nuraski.pl/wsg/userfiles/zudajimobowutome.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa314ba3427---bexitadujive.pdfIn PDF document text
    • https://aartipalette.com/userfiles/file/zitebi.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/gemozuz.pdfIn PDF document text
    • http://qa-whg.net/upload/files/levirodegow.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1608060ba6a480---55935866889.pdfIn PDF document text
    • http://rjt1.org/upload/files/60752515414.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/ad6g62f1s7b9lkfelrs4jq1gn3/2557058603.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/1186b9bfa8c7eeeedf3400e7dff2462d/50007023813.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/bd4494deb21c2e2ace3e27ab202f6b0f/jagemumavokum.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160805b731230b---zadojorenonelosirikajatak.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/e6557ac7e02c61949433cd839a3cea2f/mobabe.pdfIn PDF document text
    • http://architects-desk.com/uploadsfile/55112154815.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/01iflk7u9gattnnhsfq964f0a4/31564939859.pdfIn PDF document text
    • http://usateatop.com/_upload/files/93532831620.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e047b00c35---javuzigowebota.pdfIn PDF document text
    • http://astro2sphere.com/admin/images/file/nivojiwa.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9f032a9eaa---35863281976.pdfIn PDF document text
    • http://abwrva.com/uploads/files/80445826477.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/72197896517.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/uacu8hbeqri0tg19bo70tgr2n6/79441332529.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/35713709601.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/lagomusoz.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607e917ad5020---45790696327.pdfIn PDF document text
    • https://118highschool.am/wp-content/plugins/super-forms/uploads/php/files/07d128fb68e2f9962f5a8a85afc0f411/29956509863.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=bypass+frp+09+2016+android+6+apkPDF link annotation
    • https://sharpspringwww.kinsta.cloud/wp-content/plugins/super-forms/uploads/php/files/b5b95e059780276f36dfe1bc56383fda/73592770074.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_off0001014d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1014D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11964 11104 bytes
SHA-256: 2ab3fcc0033972d66bfdad8a90f9a29e214406b03716288e84de259090e337e4
font_02_sfnt_off00013372.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13372 18796 bytes
SHA-256: dbcc05dc29b73f6c3c713e2dbaaf71e93c274df288dd6dcfddeb6244dbe416ab

Open this report in the interactive analyzer, or submit your own file for analysis.