Malicious PDF — malware analysis report

Static analysis result for SHA-256 834ad51d3eda06ad…

MALICIOUS

PDF

83.8 KB Created: 2021-09-18 17:47:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: bf3d5a727763a7c98d3c9561eb3acdbf SHA-1: 7f71ca5bbbe24f744d463fd2d8d48549fc7f86d1 SHA-256: 834ad51d3eda06adff99bdcc0ce3a0cc506be11b0b803786a8ab1228df24a10b
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' suggests the document is designed to trick users into downloading a password-protected archive, a common tactic for evading security scans. The presence of numerous external URIs, many pointing to PDF files, further supports a link farm or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://mgrenginiai.lt/ckfinder/userfiles/files/74969877301.pdf In PDF document text
    • http://intelekt.biz/uploads/pages/files/bumaralufoku.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/davukar.pdfIn PDF document text
    • http://www.ezmoving.com/file/24459626018.pdfIn PDF document text
    • http://phutungvespaco.com/luutru/files/boluku.pdfIn PDF document text
    • https://sitarasign.ir/data/file/64088668536.pdfIn PDF document text
    • http://utpcomp.ru/uploads/files/70165829478.pdfIn PDF document text
    • https://jagamimpi.info/contents/files/2576718944.pdfIn PDF document text
    • https://xn--80aesyq.xn--p1ai/files/file/21053865621.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/29125708371.pdfIn PDF document text
    • https://intersensor.ro/v2011/Files/fck_upload/file/59105423984.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/vebuwasimupekexite.pdfIn PDF document text
    • http://saydersan.com/firma/files/vumusobazozeludivebukib.pdfIn PDF document text
    • https://goodline.by/userfiles/file/84515926755.pdfIn PDF document text
    • http://lulanjina.net/upload/files/12375173612.pdfIn PDF document text
    • http://clubselectionvoyages.com/images/file/88146001962.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/gogomosuj.pdfIn PDF document text
    • http://domingo.hu/ckfinder/userfiles/files/54720998790.pdfIn PDF document text
    • http://mutamobilya.com/images_upload/files/4492080264.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a3cec2db3---87516007917.pdfIn PDF document text
    • http://iglozawiercie.pl/zdjecia/file/miworum.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/43090486497.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210911213253.pdfIn PDF document text
    • http://langmypham.com/luutru/files/jifozibowejez.pdfIn PDF document text
    • http://logistra.fr/ressource/site-image/files/ninenetopu.pdfIn PDF document text
    • http://vnationwide.com/userfiles/files/8965143444.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=fifa+14+for+androidPDF 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_off0000e164.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE164 10012 bytes
SHA-256: f862aa14bfceb98705723ec3f18a9aa997720fee62decfd779d654c915ec16c8
font_01_sfnt_off0000f7af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC1 18776 bytes
SHA-256: 6489b2acef6d7dcf67821eab42a8fc0427de960b98e03c3bcae8207d112a6f4f