Malicious PDF — malware analysis report

Static analysis result for SHA-256 0b244e0693148711…

MALICIOUS

PDF

74.5 KB Created: 2021-09-09 05:13:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 083498ade47e6bcd9e9f591f52e39264 SHA-1: 312dd8b281a61e7eda50f1cea3d7585843fd823c SHA-256: 0b244e069314871102143fee108416548dc02ac0e1c8e87b48b0dae3ad84ce72
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable domains, suggesting a phishing or malware distribution lure. The embedded URLs point to various PDF files hosted on potentially untrusted domains, reinforcing the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://cafesezony.ru/fck_editor_files/files/73276473716.pdf In PDF document text
    • http://d2dgroup.net/upload/files/buruvafixidojuzopiwek.pdfIn PDF document text
    • http://freewest.at/34905747662.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210904141836425.pdfIn PDF document text
    • https://swapnauraan.com/ckfinder/userfiles/files/10768870886.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16132d8e4c44d1---94607374349.pdfIn PDF document text
    • http://linyuepharm.com/upload/files/vitorumidopilisubakori.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/8695673558.pdfIn PDF document text
    • http://f-kcc.jp/user_data/userfiles/files/balidudutonaruratufeva.pdfIn PDF document text
    • https://www.caissedesecolesdu5eme.fr/backoffice/ckfinder/userfiles/files/22391792656.pdfIn PDF document text
    • http://ksiclub.org/projects/achievemore/admin/upload/fckImages/file/56293514761.pdfIn PDF document text
    • https://briljant-maleri.se/UserFiles/files/gomire.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/29515909278.pdfIn PDF document text
    • http://awfiowv.love-mrt.com/upload/files/sekovimufopexolabunitek.pdfIn PDF document text
    • http://www.sm.ac.th/ckfinder/userfiles/files/xozetes.pdfIn PDF document text
    • http://esejsc.com/upload/files/didixakiximawaf.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/4985680789.pdfIn PDF document text
    • http://mocphatreal.com/assets/images/ckfinder/files/36138479657.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/0a7c1212500222f1761f93220b8ffb5a/70033904106.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/zivegaxadaxovobizumor.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/90688939193.pdfIn PDF document text
    • http://xn----7sbbgprpk7biiq.xn--p1ai/admin/ckfinder/userfiles/files/lusegujulodos.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/juzepowasafuwujedorufifel.pdfIn PDF document text
    • http://kronospan-mofa-hungary.hu/editor_up/kukexitosegomivi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=justsystem+atok+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_off0000b905.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB905 19436 bytes
SHA-256: a4a2bbb248673dc19d1c64972357319cf24a234f64f7f4903b1c9500de18e4db
font_01_sfnt_off0000ec16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC16 10660 bytes
SHA-256: 4a636371d336251f192d8cf26be5dee16450d3df908373c3f325e3aec74280fc
font_02_sfnt_off00010499.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10499 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1