Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b35007f7e07232…

MALICIOUS

PDF

171.7 KB Created: 2021-09-17 07:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 887481bd5abbd6b86840de3a212f1017 SHA-1: 5c9efdb1fa8d77e5b37e9ff6794099e8357fc057 SHA-256: 77b35007f7e07232d1e9c6d95da70e03de9dc6eadb52123f020370998cd84d5c
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links to external PDF files hosted on various domains, many of which appear to be disposable. The presence of embedded JavaScript and the high number of outbound links suggest an attempt to download and execute a secondary payload or redirect the user to a malicious site. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://workinhotel.com/upload/fckfile/3169188051.pdf In PDF document text
    • http://xahuaheng.cn/userfiles/file/49052838605.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/sebometaxebe.pdfIn PDF document text
    • http://demkapi.com/resimler/files/baxoganisibol.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16138ca4938c67---54828314261.pdfIn PDF document text
    • http://www.patriarca-batiment.com/ressource/site-image/files/60625283348.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/todovixipilosaposisur.pdfIn PDF document text
    • https://geniodelweb.com/file/80906937540.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/34127633953.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/48045441730.pdfIn PDF document text
    • http://zaiger.ru/img/file/bonoxepeze.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/zimukopofuxuxusuwis.pdfIn PDF document text
    • http://najlepsietorty.sk/uploads/fck/file/rokigexiromawijudore.pdfIn PDF document text
    • http://www.tokyomagic.jp/images/library/File/tofegarara.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/95768848925.pdfIn PDF document text
    • http://dspec-car.com/js/upload/files/gamunokozaxu.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/02135557400.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/59326156362.pdfIn PDF document text
    • http://mmprogetti.it/userfiles/files/91122253064.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/93935481347.pdfIn PDF document text
    • http://datong-travel.tw/upload/ckeditor/files/20210903233401.pdfIn PDF document text
    • https://rendszergazda-cegeknek.hu/ckfinder/userfiles/files/7214515492.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a7786a9542---lojoguranutiletasuxudiwu.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/sukarijugepenufawixebo.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/jimiwasuxigufixugulenopa.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/38004458936.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=julie+garwood+the+prize+read+onlinePDF 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_off00023534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23534 10740 bytes
SHA-256: 3147e6da4b58e8a75de3703fc8b23fae665e200fa15d63c2f720f3a3658fc0fd
font_01_sfnt_off00024db5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24DB5 22700 bytes
SHA-256: 54f56f8d053efeda5eaed43ad6d4bc3bee56ce8e3fbc3b99cdb050e5e6005e42
font_02_sfnt_off00028854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x28854 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1