Malicious PDF — malware analysis report

Static analysis result for SHA-256 e21f9ba96fe8828a…

MALICIOUS

PDF

88.9 KB Created: 2021-10-10 01:44:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 8ad1820582bd96de9ba0a7ba69256ffc SHA-1: 1bdf68dd2810d7ddf213ba6b2efb141f7b7f73fa SHA-256: e21f9ba96fe8828a39151e4aef39ff4a689dae24da07592ffbb19990bea91b0f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document contains numerous links to distinct, potentially disposable hosts, suggesting a tactic to distribute malicious content or phish for credentials. While no scripts were explicitly extracted, the presence of many unknown URLs points to a likely attempt to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 http://www.de.ruben.pl/ckfinder/userfiles/files/nitezuwezurulejoferib.pdf In PDF document text
    • https://riolisboa.com/images/ul_files/file/hQDoqCjMBpV1.pdfIn PDF document text
    • http://toptoptraining.ru/img/upload/file/rajanim.pdfIn PDF document text
    • https://ebus.myskoolapp.com/FCKeditor/FCKimgUpload/file/61098183643.pdfIn PDF document text
    • http://ecogestval.es/userfiles/file/80762557926.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/pidexewikejebalumetadiz.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/gaviro.pdfIn PDF document text
    • https://casaalu.com/luutru/files/vifaxowigulurepox.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/12118814383.pdfIn PDF document text
    • https://helices-evra.com/userfiles/file/tosonumaforawigojaxo.pdfIn PDF document text
    • http://jgweld18.com/UploadFile/file/20210909113729287.pdfIn PDF document text
    • https://firsathosting.com/calisma2/files/uploads/rejasutodijagetaf.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/7a8gggvjvtl172cqqlc3puguqi/maxeme.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/87967518222.pdfIn PDF document text
    • http://nachhilfeschule.havonix.com/ckfinder/userfiles/files/13561470851.pdfIn PDF document text
    • http://hasyo.net/files/file/1743319852.pdfIn PDF document text
    • http://thietkevang.com/upload/files/90704324395.pdfIn PDF document text
    • https://castel.ro/userfiles/file/selipubaxomabuvulirateki.pdfIn PDF document text
    • https://thietkeweblongan.com/upload/files/kebesadodararerakusuxufus.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ba3d44688---55345015523.pdfIn PDF document text
    • http://rehahomecare.com/upload/editor/files/todixufavabu.pdfIn PDF document text
    • http://nktrading.qa/file/files/bavipegesuj.pdfIn PDF document text
    • http://dietaltop.com/userfiles/files/dexikidezinozatipe.pdfIn PDF document text
    • http://studiosiciliani.eu/userfiles/files/vezoje.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/kesotiwajijuzog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=how+to+play+black+ops+4+zombies+offlinePDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/gijami.pdfIn PDF document text
    • 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_off0000f3ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010c05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C05 11100 bytes
SHA-256: 072deb51902b3b13fef00f572eefb1b9d765503635c5773017c3f6506072d3ca
font_02_sfnt_off000125cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125CD 18492 bytes
SHA-256: d0d6f8c37e3bc6cb9a36869011dd8477acc4a82ddcc42273ef069a10c4fe27d3