Malicious PDF — malware analysis report

Static analysis result for SHA-256 2164fcfb9ecf9a14…

MALICIOUS

PDF

95.5 KB Created: 2021-05-10 13:44:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: b7064455c3318305a31b6bbb2cdd9c34 SHA-1: 22f5189c67fbb5d841b65db05b576f725c0043e2 SHA-256: 2164fcfb9ecf9a14da960ee2ac155605bd38a570b519385afe6eb84fcb0cdaf9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous embedded URLs, with at least one, 'https://jottigo.ru/strik?utm_term=sense+and+sensibility+book+cover', pointing to a suspicious domain associated with link farms and potential phishing. The document body, though heavily obfuscated, suggests a lure related to 'Sense and sensibility book cover' and mentions 'wkhtmltopdf', hinting at its generation method. The presence of external URIs and the link farm heuristic strongly suggest this PDF is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 https://jottigo.ru/strik?utm_term=sense+and+sensibility+book+cover PDF link annotation
    • http://poxedon.22web.org/zopamameruxaparerawuvawi.pdfIn PDF document text
    • https://cdn.sqhk.co/bipozipo/tygiheN/rope_ninja_hero_mod_apk.pdfIn PDF document text
    • http://kibesamifi.getenjoyment.net/83445422731.pdfIn PDF document text
    • http://grandov.pro/jinubunlfsx3.pdfIn PDF document text
    • http://vehicleusains.com/38810012956uhvmk.pdfIn PDF document text
    • http://zalavsky.ru/97459453804gr1jm.pdfIn PDF document text
    • http://ninotekega.mygamesonline.org/indonesia_capital_market.pdfIn PDF document text
    • https://cdn.sqhk.co/tizalenifo/ihhljh8/christmas_adding_worksheets_ks1.pdfIn PDF document text
    • http://koparikamoze.scienceontheweb.net/53347069782.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/fdd3d814-d8f1-480b-9dcb-1775d337fdee/sketchup_online_registration.pdfIn PDF document text
    • http://jaxunukologefis.onlinewebshop.net/17799799475.pdfIn PDF document text
    • http://zafokofebub.epizy.com/dobeve.pdfIn PDF document text
    • https://s3.amazonaws.com/jobavo/calibrate_logitech_extreme_3d_pro_mac.pdfIn PDF document text
    • http://vuxawov.rf.gd/business_plan_to_start_a_restaurant.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/03f34377-789c-4964-9a89-a787bc0e6bc7/what_causes_the_plates_to_move_apart.pdfIn PDF document text
    • https://s3.amazonaws.com/zijivevip/captive_prince_volume_3_docdroid.pdfIn PDF document text
    • https://s3.amazonaws.com/gezetega/casio_ctk-2400_price_canada.pdfIn PDF document text
    • http://fijonomun.rf.gd/bluejacking_abstract.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b86cd50a-59af-43ea-af5d-8baa13a15560/connect_wh-1000xm2_to_pc.pdfIn PDF document text
    • https://s3.amazonaws.com/vizegemawokaxe/the_stanley_hotel_bear_in_lobby.pdfIn PDF document text
    • https://s3.amazonaws.com/firigugixujotov/rocky_2019_full_movie.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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000116f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116F1 5404 bytes
SHA-256: 1296204c4abe02a5f5165c590f3f1c84aee33245ef952a295e42a5bdd3c58310
font_01_sfnt_off00012962.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12962 2236 bytes
SHA-256: 6b2d3c5f6256688f626d058edaec36c164b6f3560f9078c09021343a121ddc15
font_02_sfnt_off00013391.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13391 10704 bytes
SHA-256: 63d43d27f54efdc0557e50440221e7079bb4f655b5c09b3cdf9ec38838c249a9
font_03_sfnt_off00015848.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15848 16312 bytes
SHA-256: bf8f9ece8d9d74ce2d7a98a07ee1bb8f4056faf702b3b1702118181e85f1b939