Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5fbb3c08f3092de…

MALICIOUS

PDF

88.2 KB Created: 2021-07-03 17:31:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e144a51ca218226311639901a0fdb2df SHA-1: 7da04e8ef48f3e4515d6a2597011f9e903d84c9b SHA-256: a5fbb3c08f3092de71f520fbf1195f8ec52142e9f3803b19828544c3e6d25e03
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the presence of external links and the overall heuristic profile points to a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://medvor.ru/uplcv?utm_term=shortness+of+breath+and+feeling+sick
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d64b270992---11868526321.pdf
    • https://kimtuong.vn/isc/public/files/fckupload/file/ravudotonexunapo.pdf
    • https://quickonboarding.com/wp-content/plugins/super-forms/uploads/php/files/8004acbc4ab6d2d9cb1c5c6dc32bf16c/93260247155.pdf
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f6db099e89---59906339630.pdf
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/94866499863.pdf
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160d2db72e4bba---81514323779.pdf
    • http://aquatrustfina.com/userfiles/file/26923167854.pdf
    • http://mikomisushiwc.com/uploads/files/bajewuluduzi.pdf
    • http://neboskreb-irk.ru/uploads/userfiles/files/45038260752.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/ugpe8fe1btrikv42rvriia0677/30016062770.pdf
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/34e702e0d3e4950d1d9ab1f901d6fd4e/ravekekawi.pdf
    • http://tomaszfilipczak.pl/userfiles/file/vavazimefizotakowo.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/6566cb70e4f3458892fe9e28c21f58ec/fozonaritunoxiropegixini.pdf
    • https://ambulatorioveterinariosismondi.eu/file/98939525997.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/p2p8gi439qd7vpdg567negnv5u/lusasedawev.pdf
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/16082db8abf759---43681024960.pdf
    • https://hostingalani.com/calisma2/files/uploads/ninubamab.pdf
    • https://corpusbg.com/files/fck/file/wiwetodezox.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/43h9jr100q1ac2mupm5egcagl4/nibusezisesipomoteburibut.pdf
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/2dac8c2a069fc2158e82201fc002e1ab/jejajuninejedalul.pdf
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d42d1417b---paruvasopobenulozif.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/dde01da0f3124707d0d2d45b99babeeb/52634611311.pdf
    • http://nordicaluminium.ru/userfiles/file/vuzavumejinefu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • 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_off0000f485.bin
18ff926c89953f55040301a3b5e7006cee65f515e26177437ab3afb592cc4a4e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF485 11060 bytes
font_01_sfnt_off00010df6.bin
219e3342cbebf17d754013ed0416fc4f6e71ee31352407eab8060600efdf8ddc
pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF6 17344 bytes
font_02_sfnt_off00013b48.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B48 16792 bytes