Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fa514c3fd397a54…

MALICIOUS

PDF

77.2 KB Created: 2021-09-24 06:05:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3b96feb0f734f31f5d135a5b4678288f SHA-1: 356c32767a060b54d1a859a86b4b29bfccb70d97 SHA-256: 8fa514c3fd397a54d23cc5841c38252c7c068c05ed178d844aa355a5d23f9b44
134 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. This script likely redirects the user to external URLs, such as the identified `https://coretry.ru/uplcv?utm_term=play+store+pending+download`, which are associated with phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, supporting the classification as a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=play+store+pending+download PDF link annotation
    • https://traicaygiasi.com/Images_upload/files/roxufaxamikarimabafofaw.pdfIn PDF document text
    • https://www.ruchya.com.tw/upload/files/nuxajukasevikilonivopor.pdfIn PDF document text
    • http://instit.ac/ckfinder/userfiles/files/nesigojelagifesazusapugin.pdfIn PDF document text
    • http://nedvizhimost-v-sharm-el-sheikhe.ru/uploads/files/rutufegidibifinunuvifir.pdfIn PDF document text
    • https://ibexquimica.com.br/ckfinder/userfiles/files/linowitozegu.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/15372477044.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/20698695344.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/93120040370.pdfIn PDF document text
    • http://ladyqueen.it/userfiles/files/pasoz.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/jevudurisu.pdfIn PDF document text
    • http://tlumacz-bialystok.pl/pliki/file/zovijojukajevomuvegikazi.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/48491697003.pdfIn PDF document text
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/42030241402.pdfIn PDF document text
    • https://noble-program.site/js/ckfinder/userfiles/files/4987229273.pdfIn PDF document text
    • https://goooinggroup.com/userfiles/files/20210922_161836.pdfIn PDF document text
    • https://websbag.com/uploads/files/vajavove.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/tevosojagov.pdfIn PDF document text
    • http://autosvilar.com/uploads/ckfinder/files/91853992909.pdfIn PDF document text
    • http://kondicionery-pushkino.ru/upload_picture/file/94310621397.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/fezikimanos.pdfIn PDF document text
    • https://festacontinua.it/public/file/kunijig.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614a232a9f11d---20041660528.pdfIn PDF document text
    • http://onroerendgoedindex.nl/images/uploads/18136396125.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/161335773e6d7a---1144186624.pdfIn PDF document text
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/44413150912.pdfIn PDF document text
    • 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_off0000cc10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC10 10768 bytes
SHA-256: d4646bfc38243b2558cd86ba68957759e12637ed7e80047889a4b208db25acce
font_01_sfnt_off0000e4dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fcef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCEF 16588 bytes
SHA-256: 77430fac280acf967b70952e6bb5ece2adc829b14a6f488e411953cd41570e93