Malicious PDF — malware analysis report

Static analysis result for SHA-256 f956916bbabd7381…

MALICIOUS

PDF

85.3 KB Created: 2021-09-08 18:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 646cf89e492e38de9025914cb0fac1ad SHA-1: 06caf733545870386f1296cbb2c4a5448cef7cc3 SHA-256: f956916bbabd7381f1f2aff59cabc30e44c7df6f2a22e875ee44d4d23baac6e8
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to files hosted on domains associated with compromised CMS uploads or disposable hosting. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is part of a link farm designed to direct users to other potentially malicious documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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 http://hejia-ele.net/upload/sibegixo.pdf
    • https://karatenarrewarren.com.au/ckfinder/userfiles/files/10775185618.pdf
    • http://tcihk.com/userfiles/59879089906.pdf
    • http://xn----8sbaqfskngn1qi.xn--p1ai/userfiles/file/11422771071.pdf
    • http://bertrandetgastineaudesigners.com/userfiles/file/zosorezikaxebez.pdf
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161365bbba1f3f---kurevorabeweka.pdf
    • http://nprofit.hk/userfiles/porumovovowozubapimuja.pdf
    • http://mlsconsulting.net/cms/files/File/gajitenokut.pdf
    • https://quatden.vn/webroot/img/files/86054464180.pdf
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161379b9aa1f70---lisujimunurekufegin.pdf
    • http://nessium.fr/userfiles/file/xapapogoxurolaguwudepil.pdf
    • http://cycling-software.com/files/file/robazegagovokasopid.pdf
    • https://maximatrimony.com/ckfinder/userfiles/files/28605472740.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136b205051ce---1210927758.pdf
    • https://partetesal.ir/data/file/paxagetegoduzekofulanetu.pdf
    • http://dragonera.cn/admin/userfiles/file/7131537538.pdf
    • http://flemingdecal.com/uploads/assets/file/padumukixenulol.pdf
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161352faae61fa---rixokuvupadutegab.pdf
    • https://bda.ch/ckfinder/userfiles/files/fejozibipixemoresedomesum.pdf
    • https://ofly.om-digitalsolutions.cn/upload/files/ruvelovaxuru.pdf
    • http://hangquangauto.com/files/88866912113.pdf
    • http://mylivediamondinventory.com/uploads/files/42971273654.pdf
    • https://www.karenlovelee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d35e4ece7---94472045782.pdf
    • https://buyafranchise.org/files/files/36367521386.pdf
    • http://remobudostol.pl/pliki/fenepeza.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=psychologie+sociale+du+travail+et+des+organisations+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_off0000dfe3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE3 16792 bytes
font_01_sfnt_off0000f7fa.bin
21a2b5c36cc81a873ff9cdfdaf330791f597e90368ca27152fe05a9538c889ba
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7FA 11180 bytes
font_02_sfnt_off000111ed.bin
f36d60a22cd0b50319cb7b0e49ffa0792d245bd1e06b877fd63d858958e916ba
pdf-font-stream PDF embedded font (sfnt) at offset 0x111ED 19940 bytes