Malicious PDF — malware analysis report

Static analysis result for SHA-256 037a883d128c6cd5…

MALICIOUS

PDF

95.1 KB Created: 2021-09-12 03:17:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d552864a78016d80987da6914905f925 SHA-1: 9e8a2e1701ae07f9fa167bd01642d67db8efe0a3 SHA-256: 037a883d128c6cd51a78754c810c294cad9939f3c7b07a10de56f093db2dff38
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the nature of the heuristics indicate an attempt to lure users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

Heuristics 6

  • 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.
  • 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://infrive.ru/uplcv?utm_term=how+to+set+birthday+reminders+on+android PDF link annotation
    • https://bangvetthuong.com/luutru/files/79422410906.pdfIn PDF document text
    • http://kingsap.com/file_media/file_image/file/noraduvogikutumogibari.pdfIn PDF document text
    • http://www.ssc-ras.ru/ckfinder/userfiles/files/49947829909.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161368377d1a36---25718947858.pdfIn PDF document text
    • http://rungrawin-itt.com/userfiles/files/69107032736.pdfIn PDF document text
    • https://groupunsur2.com/contents/files/37653646810.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/44634614656.pdfIn PDF document text
    • http://clinicaveterinariamontecchia.com/userfiles/files/7981924397.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/28173037905.pdfIn PDF document text
    • http://suliaok.com/v15/Upload/file/2021912720172480.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/vuxumefozeva.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/65613add6c1f93d774673db70160b953/2460326080.pdfIn PDF document text
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/iddorvsn8cjqceoq6smd8g1pig/78753585314.pdfIn PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/kcd6u2svqhrhvgf4ratappcke5/fabusebifawalofolidoge.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/36850067081.pdfIn PDF document text
    • http://bosch-elektronarzedzia.pl/catalog/file/kuvupulujafetokikexo.pdfIn PDF document text
    • https://loyalangkorapartment.com/userfiles/file/zofij.pdfIn PDF document text
    • https://aashianarealty.com/file/23052554472.pdfIn PDF document text
    • http://portableandcool.com/files/files/63724284962.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612f0e23ca676---nagitesix.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/mumaxidijoz.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/jododa.pdfIn PDF document text
    • https://catwalkdogcome.com/editor_upload_image/file/3993120289.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613d44aecbc94---2456726247.pdfIn PDF document text
    • http://15449010.com/FileData/ckfinder/files/20210904_D7321C0F15E400D3.pdfIn PDF document text
    • http://slovbau.sk/test/userfiles/file/musiziwif.pdfIn PDF document text
    • https://ipic.vn/userfiles/file/6025537021.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/hcue1qp194n1dd0pl742hvcnrc/27516189502.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_off00010d1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D1E 18700 bytes
SHA-256: b1884725d42c6e51931aebfb5270cd0b66a44e2cc90484d10ba2a0dacc2edb74
font_01_sfnt_off00013d50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D50 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15567 10796 bytes
SHA-256: 45de3e8fa0793da801d49dd5e5e2ce05b91c798a5f70887bf86c274c7ff549d4