Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1d0a03eabb32ce2…

MALICIOUS

PDF

74.3 KB Created: 2021-09-14 09:06:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 85278e08a92903f55722e851ad34ceae SHA-1: 9ce1ee51edc84fb4771ca7c6d3f891402d21c50c SHA-256: c1d0a03eabb32ce236bb140ec5475273899cc16e91c59fc7f845b1ab4f1f2751
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It functions as a link farm, with numerous embedded URLs pointing to various websites. Several of these URLs are hosted on compromised CMS platforms, increasing the risk of users being directed to malicious content or phishing pages. The PDF structure and the nature of the URLs suggest an attempt to lure users to external sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://karaokejdi.com/ckfinder/core/connector/php/upload/files/78309945257.pdf In PDF document text
    • http://aristosaigonhotel.vn/uploads/files/83545005825.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/92417918369.pdfIn PDF document text
    • http://dralituncer.net/userfiles/file/99770783933.pdfIn PDF document text
    • http://shipsupply.ru/userfiles/files/65450474816.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133a6258ce0b---rijad.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5d15ef586---jibejuvonabamarova.pdfIn PDF document text
    • http://ndt-ultratech.com/files/rikugumedobewuso.pdfIn PDF document text
    • https://novamakine.com/upload/ckfinder/files/vonapi.pdfIn PDF document text
    • http://medicamarsala.it/userfiles/files/veledo.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/lufatixusanatizebosi.pdfIn PDF document text
    • http://domplus.su/userfiles/files/kopifeludaxume.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161395e5f2787c---sexudedugoxonen.pdfIn PDF document text
    • http://kindergartenhelden.at/upload/file/wirodinerexomobe.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/zumupedi.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/62772439667.pdfIn PDF document text
    • http://chinazzjx.com/d/files/17464631006.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/49062682611.pdfIn PDF document text
    • http://njboyuanchem.com/upload/files/wasuzanudamugejevilep.pdfIn PDF document text
    • https://digireg.it/upload/bepineguvutuvapa.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb1ca6015f---rudowejasijatalosupaxezo.pdfIn PDF document text
    • https://rozynoklinika.lt/userfiles/file/10572516750.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=anime+crossover+games+mobilePDF 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_off0000bf8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF8E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d7a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7A0 16904 bytes
SHA-256: e900c384074ca01f6a8dd59456e1c7cbc24b6be1150e548e563ffd638ad67c1a
font_02_sfnt_off0001034f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1034F 10664 bytes
SHA-256: 26ee885c9e949373843b2565094841a87d64b84bc5e13d90bb50533fe2c5f7b9