Malicious PDF — malware analysis report

Static analysis result for SHA-256 e7a1429dc6320d42…

MALICIOUS

PDF

70.5 KB Created: 2021-10-02 17:49:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 1581ba58443ccb59dfa2a72de0e8b125 SHA-1: 7731a211bce15e92129162c5484423db92e14a18 SHA-256: e7a1429dc6320d428f65ae3f14a7c9da623a8681205aa8c976e8bb71766576c8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a heuristic firing for PDF_SEO_DISPOSABLE_LINK_FARM indicates it is a link farm with many distinct hosts. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to redirect users to phishing or malware download sites. The embedded JavaScript may be used to facilitate this redirection or exploit PDF vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://leonardscopysystems.com/home/leonards/public_html/ckfinder/userfiles/files/koturekub.pdf In PDF document text
    • https://goodnest.info/tctt/sites/aaa/file/voluvemojodo.pdfIn PDF document text
    • http://yuh-tarng.com/userfiles/file/renevelididod.pdfIn PDF document text
    • http://mindentudor.hu/userfiles/file/2048819288.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/84697851696.pdfIn PDF document text
    • http://www.idukkidiocese.org/files/js/ckfinder/userfiles/files/36899869015.pdfIn PDF document text
    • http://ellenia3.eu/userfiles/files/96723847096.pdfIn PDF document text
    • https://inprovitvenezuela.com/ckfinder/userfiles/files/gumegolebisizagirodati.pdfIn PDF document text
    • https://plentis.eu/ckfinder/userfiles/files/losagu.pdfIn PDF document text
    • http://csc0731.com/userfiles/file/20210927064722_kd8g02.pdfIn PDF document text
    • http://irvine.songhakbbq.com/uploads/files/53408820391.pdfIn PDF document text
    • https://aep-tc.com/cache/fck_files/file/44366133009.pdfIn PDF document text
    • http://bioident.pl/photos_fck/file/73499200348.pdfIn PDF document text
    • https://www.psk.com.au/application/third_party/ckfinder/userfiles/files/xodilovotevo.pdfIn PDF document text
    • http://studiobaldizzone.com/userfiles/files/wifobujuwomerazevomuruf.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16141a8a12f984---gopolulilosej.pdfIn PDF document text
    • http://poliinc.com/upload/files/86776168664.pdfIn PDF document text
    • https://nabijdefossa.nl/upload/files/ravoluwezujewemavubapu.pdfIn PDF document text
    • http://sportservistocik.cz/UserFiles/File/rupepudelapijibejawevewis.pdfIn PDF document text
    • http://car-zone.sk/data/data/file/rupapil.pdfIn PDF document text
    • http://attep.com/home/sandbox/domains/heekee.com.hk/public_html/ckfinder/userfiles/files/10357277305.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/81168818648.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614b73dd00cb7---tujixuduneronifunawifodud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=identifying+simple+compound+complex+and+compound+complex+sentences+worksheet+pdfPDF 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_off0000afbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7CD 15932 bytes
SHA-256: c974851b8601047b5111ecce5c714fa41563119de22e2a2979e7e8fb94c99c86
font_02_sfnt_off0000f0c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C6 11512 bytes
SHA-256: 285e3de3c3b3c7c6347625b9ddb29e4cbb814dfc38fc458c30cae91e9bc420f7