Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4aecb76db941a4e…

MALICIOUS

PDF

76.9 KB Created: 2021-09-04 05:35:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8085f203e0b765ad63938d8b44831a7c SHA-1: 06bcdb864830d4ada43a168b030cc453a5d1c8b0 SHA-256: b4aecb76db941a4e97915fb399ccca9c3e587e4f631016e91b623ac835f0e869
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to potentially harmful content. The presence of these link farms and the overall structure strongly suggest a phishing or malicious redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://5uempat.com/contents//files/16315547711.pdf In PDF document text
    • http://kapelski.pl/userfiles/file/mikodawo.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/68965678456.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/rexesovulezat.pdfIn PDF document text
    • http://sun-tes.ru/files/file/zelepematepitixomuwurofam.pdfIn PDF document text
    • http://101eyewear.com/luutru/files/vudorakap.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/3f3kbt90rpqe433lak5bsbangp/joxewovegadudoroxixum.pdfIn PDF document text
    • http://robbinsfamilyhealthcare.com/clients/2/2c/2c787fa606fc56c3a3a24dfc5409695f/File/simaro.pdfIn PDF document text
    • http://azseal.net/uploads/userfiles/file/34034994226.pdfIn PDF document text
    • https://tdfstore.it/file/fukanolo.pdfIn PDF document text
    • http://rioairporttransfer.com/ckfinder/userfiles/files/27762348348.pdfIn PDF document text
    • http://laweasy.kr/userfiles/file/juxikuxofutabejewuduruv.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/sabc0m64bbkm4g4kfvgpfn12r5/sokomi.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/57528601732.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/dj753oipbpfj61g14o7q9j2or4/muperinopaku.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/7213148333.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/lezonolufidirekibisewuma.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/slighdsgrgqc63h8beppdof5dv/gezuwarosabiwixejejesa.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c42f4b2d3f---58673533354.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/fbb9024d666d90500b4d93442263c3e7/33229901832.pdfIn PDF document text
    • http://artkulinaria.pl/sites/default/files/file/7427479253.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/55710498020.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160812dae09a56---pilijupidikuvupukijululut.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/57037034303.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607caacc97c5a---tatiruka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=worksheets+on+interrogative+pronounsPDF link annotation
    • 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_off0000c5fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5FE 18212 bytes
SHA-256: 366f91ccbaf30bbcac4c0972df213e6da98a786830173e89bb944897bb7f216c
font_01_sfnt_off0000f4a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010cbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBE 10736 bytes
SHA-256: 4de70e6cfc9a0916ac3900c14d400e06648e5dad057d7e941b84877cbea3ff33