Malicious PDF — malware analysis report

Static analysis result for SHA-256 58a36dedd646e888…

MALICIOUS

PDF

70.7 KB Created: 2021-09-30 16:11:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3549d458c7fb24d503f0b78466458516 SHA-1: 149b17346d2ff91c5ed4aca3933d83b1c6743f14 SHA-256: 58a36dedd646e8888e28922e116a7ead39a64a8b547ad9a6ca8e531cd6e3e31e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains embedded JavaScript and numerous external URIs, many of which are hosted on compromised websites. These links appear to be part of a link farm designed to direct users to download potentially unwanted or malicious software, as indicated by the ClamAV detection and ML classifier flagging. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5748

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://krisoc.ru/uplcv?utm_term=office+2016+free+download+with+crack+full+version
    • http://dreamsurgerycn.com/ckupload/files/marotozu.pdf
    • http://hnkingdee.cn/Files/file/202192302419.pdf
    • http://otworz-biuro-podrozy.pl/userfiles/file/83708223506.pdf
    • http://makesomenoise.hu/upload/file/62299342652.pdf
    • http://filtrydokoparek.pl/img/all/72741231322.pdf
    • http://aptekarynek.pl/zdjecia/fck/file/gunekewebaxarilobenafow.pdf
    • http://celeb.huh.hu/UserFiles/File/86551887900.pdf
    • https://dukeofmarshall.com/ckfinder/userfiles/files/pulelel.pdf
    • https://emenu.hu/editor_up/55193664631.pdf
    • https://triangle-electronics.com/assets/userfiles/file/kaxasevitar.pdf
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16134db179f8e4---55016400294.pdf
    • http://nhatrangpalace.net/app/webroot/upload/files/vajomutitisipizewasito.pdf
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/92e172b841f30be3aaf985815b2114f7/fatile.pdf
    • https://sensormaticltd.com/app/templates/js/ckfinder/userfiles/files/mimomuk.pdf
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/16155b42d701b3---podujanarum.pdf
    • http://fusiongrup.ro/userfiles/file/6418424083.pdf
    • http://krukaiart.com/userfiles/files/tosipipetuzeg.pdf
    • http://webursitet.org/Files/file/tebejuliwizibo.pdf
    • http://www.fullertherapy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615233aff0b83---76079127674.pdf
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c4d358e6f---bikavilanenovenezuveto.pdf
    • http://gymostrov.eu/gymostrov/userfiles/file/64081633988.pdf
    • http://www.bufolari.com/public/immagini/file/pefunerutanategivubidobe.pdf
    • http://gewald.ru/content/Files/58746806351.pdf
    • https://daulte.com/ckfinder/userfiles/files/lexisorukup.pdf
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b6a2.bin
b4e8372a7d6b48258c4caf93a94c56d73f26ad76f3cf878eb6e67e9c3fd50a63
pdf-font-stream PDF embedded font (sfnt) at offset 0xB6A2 16888 bytes
font_01_sfnt_off0000e25d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE25D 16792 bytes
font_02_sfnt_off0000fa74.bin
6c1d1248c9eaacbf763dd6689e2dcee771c29667527f2ba3f529776f95216ffa
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA74 11404 bytes