Malicious PDF — malware analysis report

Static analysis result for SHA-256 8379d913bb423f55…

MALICIOUS

PDF

90.8 KB Created: 2021-09-22 21:33:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 389d774bc2759c6a1d649558b13a1785 SHA-1: b09e7611b77a289e4981955ac00a1179d601c743 SHA-256: 8379d913bb423f55f20de7b190c0ad6b5043385d59c2594cffe18de12fe9a235
176 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Numerous heuristics identified the document as a link farm, with many external URIs pointing to potentially compromised websites or disposable hosting. The primary purpose appears to be directing users to external resources, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://pistant.ru/uplcv?utm_term=click+start+4+computer+science+for+schools+pdf
    • https://cingenito.ca/upload/editor/file/vazofalagitusutides.pdf
    • https://shopexpert.com/app/webroot/files/userfiles/files/67542807161.pdf
    • http://niktid.ru/userfiles/file/98047547304.pdf
    • https://adetexfoamgroup.centralcms.cloud/galeria/files/vujexikodigigef.pdf
    • http://rasciindia.com/firetech/ckupload/files/fupetedageladotolujared.pdf
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/acb0846e76aa0c5f4520596f400e561d/dedilukifaxujunalarazawus.pdf
    • https://pastelbuilders.com/userfiles/file/87847558964.pdf
    • http://www.impactit.in/ckfinder/userfiles/files/26486378093.pdf
    • http://sun-apartments.pl/data/pages/talexipuxutuderowokevumaj.pdf
    • http://club-integra.ru/userfiles/file/kefukedaxodixip.pdf
    • https://www.educazionesessuale-scuola.ch/ck/ckfinder/userfiles/files/finefurepini.pdf
    • https://narellesastro.com/userfiles/files/furonozumepi.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613cf36aa35db---zupofiduz.pdf
    • http://sterenstein.ru/userfiles/file/muleleforipuvenuto.pdf
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/0eb9d1e761fe4ad6400b674fa8202dfc/66348113926.pdf
    • http://creptiles.dk/userfiles/file/15301474891.pdf
    • https://asiastudy.in/ckfinder/userfiles/files/57086271809.pdf
    • http://seyrimerdin.com/userfiles/file/pemufobexenoge.pdf
    • https://stpm-sa.com/userfiles/file/fatajetutugav.pdf
    • http://avsa.org/sites/default/files/images/files/77130838019.pdf
    • http://okfilm.kr/userData/board/file/mipime.pdf
    • https://investmentskillsgroup.com/images/userfiles/file/pinoni.pdf
    • https://ntct.dz/ckfinder/userfiles/files/33682128294.pdf
    • http://140.121.180.103/ckfinder/userfiles/files/28491385218.pdf
    • http://golfvillageonline.com/userfiles/file/81274593846.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_off0000f8be.bin
98dfe7f7659d2385299466711d0d30e3918dc0813c32b5934bcfade4d6533cde
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8BE 11184 bytes
font_01_sfnt_off000112c2.bin
1689ef4bf4e8df14d7510f491d0a0154b45f4d386262828c51ec5b5e282ec45b
pdf-font-stream PDF embedded font (sfnt) at offset 0x112C2 19080 bytes
font_02_sfnt_off0001448f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1448F 16792 bytes