Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f18b3a2485cdd10…

MALICIOUS

PDF

87.4 KB Created: 2021-09-20 13:49:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 5fee864b5b2986ed81fb6ca802e32871 SHA-1: 7adee97a1c1503453502e9a5bacfa922dc824184 SHA-256: 1f18b3a2485cdd1019193a725b05e7e1013b2be0e7e98c7944fd341de53708de
126 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate malicious intent. The PDF contains numerous embedded URLs pointing to a link farm, a common technique for phishing or distributing further malware. The presence of multiple distinct hosts and the 'utm_term_redirector=True' heuristic suggest an attempt to obscure the final destination and potentially track user engagement.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://melz-feu.ru/upload/maxuge.pdf In PDF document text
    • https://ww150007.linebot.net/upfile/files/20210902093839.pdfIn PDF document text
    • http://blueview.nl/app/webroot/files/userfiles/files/lenodatavataxazagude.pdfIn PDF document text
    • https://jphotographyllc.com/userfiles/file/vexiwotenexatu.pdfIn PDF document text
    • https://postele-z-masivu.sk/ckfinder/userfiles/files/27857858856.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/1hvmu9i96oteg8hgp77n1cuoiv/nedavezatemefowogurusuxob.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/teviparapupipevelojup.pdfIn PDF document text
    • http://www.ap-arte.ro/fckupload/file/90390958193.pdfIn PDF document text
    • http://balone.net/_upload/file///senejunogigonugewa.pdfIn PDF document text
    • http://ekopaczka.pl/imgbrama/files/repufaxirixabon.pdfIn PDF document text
    • http://olynskiconstruction.com/pics/file/78551981681.pdfIn PDF document text
    • http://newworldss.com/uploads/file/68518837330.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/wujew.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/52787328042.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/zasutazejapejuxekatu.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/wusafefetidig.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/21268724450.pdfIn PDF document text
    • https://nepalipublisher.com/ckfinder/userfiles/files/tusamumupor.pdfIn PDF document text
    • https://aluvioneschicamocha.sinecsas.com/ckfinder/userfiles/files/93092696644.pdfIn PDF document text
    • http://elcivan.com/admin/UserFiles/file/78734756188.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/16565794577.pdfIn PDF document text
    • http://0-50.ru/userfiles/file/87305504194.pdfIn PDF document text
    • http://plan.msu.ac.th/ckfinder/userfiles/files/28358695626.pdfIn PDF document text
    • http://www.sictombbi.fr/ckfinder/userfiles/files/mogexive.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/2daaa71a72afbac6a1d582190c46a76a/zotufogirazemuvita.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=o+words+to+describe+somethingPDF 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_off0000ee95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE95 10860 bytes
SHA-256: e67d724a2734350787ca6e071bb64ed444a26c896e2e409f8a38c98951290f01
font_01_sfnt_off0001074c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1074C 18440 bytes
SHA-256: f6614fda2ca5501912d559db2b2b83d1f28efeb9c6e4e2d7d2314a2015abee94
font_02_sfnt_off00013759.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13759 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1