Malicious PDF — malware analysis report

Static analysis result for SHA-256 85663dbf9e24f255…

MALICIOUS

PDF

72.4 KB Created: 2021-09-26 01:22:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8b94a712ae5ed3321f256128e33008d0 SHA-1: 8ccb160407e1b3dd6d047855395b5b8fe9dc4254 SHA-256: 85663dbf9e24f255ff7592dd977df0b16240e9e11eaec68e017c69032c34a472
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links pointing to disposable hosting and compromised CMS upload storage, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://barcelonasixtytwo.com/userfiles/file/63046425263.pdf In PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/febetowefunob.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/69205015470.pdfIn PDF document text
    • http://didula.ru/img/file/12303088644.pdfIn PDF document text
    • http://drentmedischadvies.nl/uploads/files/87656344393.pdfIn PDF document text
    • https://mjrspot.com/fckimages/file/famebazoletisi.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/98944916543.pdfIn PDF document text
    • http://www.mezmat.ru/ckfinder/userfiles/files/pubejusibidekejetivawam.pdfIn PDF document text
    • https://sukaunited4d.vip/contents/files/85224650936.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/kanawow.pdfIn PDF document text
    • https://gkatsov.com/userfiles/file/fuxevikejofelamujuratawo.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/797f4841efe188ad47e02353cc88d814/87767844054.pdfIn PDF document text
    • http://forglass.sk/userfiles/file/sumamufurudorow.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/84784258096.pdfIn PDF document text
    • https://elnativocoffee.com/silver/upload/files/gafiloxejil.pdfIn PDF document text
    • http://aotwresort.net/ckfinder/userfiles/files/fedajapepisazu.pdfIn PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614dac2999af3---27762324713.pdfIn PDF document text
    • http://kxzyjy.com/CKEdit/upload/files/lexajaguj.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614851434bd22---5480233441.pdfIn PDF document text
    • http://say-international.eu/userfiles/file/25881337863.pdfIn PDF document text
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/4704501322.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/tugaxelerulawaxafero.pdfIn PDF document text
    • https://ssvacancy.com/ckfinder/userfiles/files/nadesiwifedebifoso.pdfIn PDF document text
    • http://a1climbing.com/userfiles/files/65470021275.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/tulopuvegivu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+synchronise+outlook+calendar+with+androidPDF 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_off0000b566.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB566 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD7D 10848 bytes
SHA-256: 0e5a1066f86ee5ffb0866cd7ea1bd46545d47302055a8ddbeb69899f63b4a5cc
font_02_sfnt_off0000e67d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67D 17552 bytes
SHA-256: 6bb60f91ca3e1cf89339cde5d5796b2d7eb97e0a58ee29fb580ee64265c97e2d