Malicious PDF — malware analysis report

Static analysis result for SHA-256 d72bd36f638b6e0a…

MALICIOUS

PDF

67.9 KB Created: 2021-09-10 08:56:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 431fd650ab3314ce171ba4074532d168 SHA-1: c8068c4227f5d75aa0a68edd2605e0bc809952cc SHA-256: d72bd36f638b6e0a67485827266043135cf2771523e53b7dd767f376ce3b2d42
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file exhibits characteristics of a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS platforms. The ML classifier strongly indicated maliciousness. While no scripts were directly extracted, the structure suggests an attempt to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • 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://careerroots.net/ckfinder/userfiles/files/nadibejav.pdf In PDF document text
    • http://www.octopus-quatuorvocal.com/ckfinder/userfiles/files/varegubomefuvi.pdfIn PDF document text
    • https://mpksieradz.pl/upload/file/20934552413.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/h815bje2tuscpiutjmrdladotv/55366663068.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613abeb4dfac3---78275794816.pdfIn PDF document text
    • https://euinsuti.ro/app/webroot/files/userfiles/files/wagejogidobavugawezimorow.pdfIn PDF document text
    • http://ageddfjtjgrade.pretty-match.com/upload/files/vovidujexuzekutajej.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/dalutiki.pdfIn PDF document text
    • https://hantverkarenisandby.se/UserFiles/files/bojab.pdfIn PDF document text
    • http://2013.letnifestiwal.pl/ckfinder/userfiles/files/28351598448.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210910102220.pdfIn PDF document text
    • http://rialta.ie/userfiles/files/lusekidazi.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/ftf366eo9v61d6k0oh17j39l91/gumidivu.pdfIn PDF document text
    • http://vicc.huh.hu/UserFiles/File/75812458919.pdfIn PDF document text
    • http://art-ball.net/files/file/52627935284.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/10064986175.pdfIn PDF document text
    • http://honyi.tw/ckfinder/userfiles/file/34645210632.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/nukerejawekisulixifim.pdfIn PDF document text
    • http://romengo.com/ckfinder/userfiles/files/pozopit.pdfIn PDF document text
    • https://middletonchambers.com/ckfinder/userfiles/files/jedomitag.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/fajoradefolixegelodoseji.pdfIn PDF document text
    • http://qcfloor.com/userfiles/file/misabizobexifalag.pdfIn PDF document text
    • https://kuepancong.com/contents/files/63962896021.pdfIn PDF document text
    • https://cowik.pl/upload/pikupovunaxavu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=mi+box+4+romPDF 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_off0000af5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC774 9872 bytes
SHA-256: 6b6395856a5bb25027ac94934f19605220afc089ce246ec7b94d809c17e407ed
font_02_sfnt_off0000dd2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2E 14760 bytes
SHA-256: 27bb1a579737456c8cde89b2f5e040021ee8c2a269299f805e22d31fde4e171c