Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b20a2ea37968bcd…

MALICIOUS

PDF

106.8 KB Created: 2021-04-05 02:10:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 14cf2f0ed48d124b4054bfe65d771a69 SHA-1: 109b7c689814cb600f791166484244eb401314f7 SHA-256: 8b20a2ea37968bcd218d52efdd7b490c7309d6d9193ca6e9e1a0629a4818109d
66 Risk Score

Malware Insights

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

The PDF document contains embedded URLs, one of which points to 'zajinet.ru', a domain flagged as potentially malicious and associated with link farming. The document body, though heavily obfuscated, contains text fragments that suggest a lure related to academic search terms, likely to trick users into visiting the malicious URL. The ML classifier strongly indicates maliciousness, and the presence of multiple external links on disposable hosting further supports a malicious intent, possibly for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 4

  • 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://zajinet.ru/award?keyword=airy+stress+function+nptel+pdf PDF link annotation
    • http://sale-siberian-force.online/best_construction_safety_certifications0jswt.pdfIn PDF document text
    • http://doweryklkq.space/zewepuvaxudonawagugilogarak4p2.pdfIn PDF document text
    • http://decideyouself.fun/fortnite_mobile_mod_menu_androidw84uj.pdfIn PDF document text
    • http://rebelliona.online/amazing_god_you_can_do_all_things6y9b7.pdfIn PDF document text
    • http://kernig.store/dyson_ball_toy_vacuum_purplerhjnv.pdfIn PDF document text
    • http://zahlungsservice-ch.site/4406321356ix3s0.pdfIn PDF document text
    • http://vorecan.space/la_historia_de_julianq3a1w.pdfIn PDF document text
    • http://idealslimitaly-ufficiale.site/tejamemiwuzrsjwa.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/3ac18695-5b95-41ba-866e-845a3c9645b4/gozizuwijutoj.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5506c419-78ff-404c-88b9-c9f6ff331fa2/dungeons_and_dragons_dice_box_plans.pdfIn PDF document text
    • https://s3.amazonaws.com/kugelilizibuwum/moto_g6_plus_pattern_unlock.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8d4724c3-ef7c-41b7-a38d-611c77849928/sijusifutumupove.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1795151-f968-4ecf-8d5b-431fead31521/how_to_see_dow_futures_live.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6c7f5ed-bf55-4bb1-957c-06f7b7f74ead/how_to_pair_kenwood_kdc-bt362u.pdfIn PDF document text
    • https://s3.amazonaws.com/fapaga/google_drive_file_stream_windows_xp.pdfIn PDF document text
    • https://s3.amazonaws.com/xirixepo/dusumajegirixelajij.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/507bd36e-5d65-48b0-9df5-a8a51dd55a00/asus_p6x58d-e_atx_lga1366_motherboard.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c79ac9a2-34e2-45ef-80d1-5f7bd163137e/80691550360.pdfIn PDF document text
    • https://s3.amazonaws.com/nademopor/zesoz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b263cd08-d9d4-4fd9-8ab2-ac18c43c618d/51873107132.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2545448-d9c5-4a76-b9e1-880a19cea139/wahl_clippers_not_working.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e2aae0e-db0a-4a3e-8cd5-dbf02e53d2aa/defozovekuzulux.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014a8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A8B 5032 bytes
SHA-256: 3a30e1499bb063a100fdccb0d14ad287c002ec6c5c415070d5c91b08bd0a5ae4
font_01_sfnt_off00015bca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15BCA 13192 bytes
SHA-256: 13b3719adae1803cd9071d0149747d9a37267fe758346c5887a70081c23cbe34
font_02_sfnt_off000188bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x188BC 16060 bytes
SHA-256: 713933360072c9d59346590fad668f98c3603c6d2b72ed941ce85481f6af0b74