Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6c1958bc3780728…

MALICIOUS

PDF

83.4 KB Created: 2021-09-12 14:30:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d8d30b2edf2dec6e8e1102f97068ddcf SHA-1: 2c1f38b12b8e7476f2a0f69ccd2b00d06702d963 SHA-256: a6c1958bc378072832ee04097fd8b2008b621df458e8b4d036a405736a40d68c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that lead to link farms, with one heuristic identifying it as a link farm on disposable hosting. The document body is heavily obfuscated, but the presence of numerous external URIs and the link farm heuristic suggest an attempt to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/f4298a3ebc0fb19061e1e5ab5d3e3e23/43915503271.pdf In PDF document text
    • http://futimisdev.com/userfiles/file/fumaduvorozozetelimelel.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/38062294597.pdfIn PDF document text
    • http://china-miyaco.com/img/file/2021912152735.pdfIn PDF document text
    • http://miydz.com/mingyi/images/userfiles/file/zafoxomuputi.pdfIn PDF document text
    • http://greenglobepms.com/uploads/bagumebulomamenu.pdfIn PDF document text
    • https://santehsevast.ru/userfiles/files/56251542393.pdfIn PDF document text
    • http://naasschoolofmotoring.ie/fckeditor/userfiles/file/vuzipese.pdfIn PDF document text
    • https://musikkursus.dk/userfiles/file/ruletumosopazafiwipabi.pdfIn PDF document text
    • http://zakuskymoser.cz/www/ckfinder/userfiles/files/65899408843.pdfIn PDF document text
    • https://pastelbuilders.com/userfiles/file/95103072426.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210904020013.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/72083172347.pdfIn PDF document text
    • https://widerbet.pl/userfiles/file/lojupefiwovob.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c06199f6a---ximakegirupudezifivivavo.pdfIn PDF document text
    • http://ljsmelt.com/upload/files/xukamesimirejugogibogex.pdfIn PDF document text
    • http://e-motyle.natura2000.pl/imgturysta/files/dutuza.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/56801174858.pdfIn PDF document text
    • https://armature.ir/cache/fck_files/file/54726810510.pdfIn PDF document text
    • https://vibangnhadat.com/uploads/files/jikawef.pdfIn PDF document text
    • https://dycmc.com/DATA/upload/files/202109040429055187.pdfIn PDF document text
    • http://gucaoyun.com/uploads/file/10215619393.pdfIn PDF document text
    • https://sportcity.bg/webroot/img/content/files/gamixowolunapi.pdfIn PDF document text
    • https://medarbindia.org/ckfinder/userfiles/files/popezonusejatirok.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/nusopusizeb.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=fantastic+beasts+and+where+to+find+them+full+movie+online+freePDF 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_off0000e05e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE05E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f875.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF875 11108 bytes
SHA-256: 8d609810704b7edc415a4645b7017e80f190b3bfa6f60068021e2f103274bc0d
font_02_sfnt_off0001123e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1123E 17300 bytes
SHA-256: e60db77f51299605f0b648ff6ba192182d9e24e1eea942413d1ac9a4437607ba