Malicious PDF — malware analysis report

Static analysis result for SHA-256 b900536970570cea…

MALICIOUS

PDF

80.8 KB Created: 2021-03-01 14:19:48 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 0fab9730b26da97fa51f37e732b4e40c SHA-1: d3f3d072cf6e6e5a968e09c5f994c6ab2b452ac6 SHA-256: b900536970570cea0f79fee782abd5300cf10c9bf80ec6daa44dadbe089f642f
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with at least one identified as a malicious redirector pointing to `https://crophysi.ru/strik?utm_term=acs+organic+chemistry+exam+study+guide+pdf`. The document also leverages disposable hosting and link farms, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than 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.
  • 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://crophysi.ru/strik?utm_term=acs+organic+chemistry+exam+study+guide+pdf In PDF document text
    • http://kirakexig.mypressonline.com/86195208383.pdfIn PDF document text
    • https://kebolegenadudus.weebly.com/uploads/1/3/1/4/131454121/tebilak.pdfIn PDF document text
    • https://sanegirorasatu.weebly.com/uploads/1/3/5/4/135400744/pefusadojeket.pdfIn PDF document text
    • http://silkhfig.bid/xinofixagojazeboxapi6zxbv.pdfIn PDF document text
    • https://nagugopusoz.weebly.com/uploads/1/3/4/6/134645600/vibiwuroxop-niwagufubavurom.pdfIn PDF document text
    • http://borejukeluteva.mygamesonline.org/20703400126.pdfIn PDF document text
    • http://kerutugizuxig.mygamesonline.org/diary_of_a_wimpy_kid_film_2012.pdfIn PDF document text
    • http://jotitojimo.mygamesonline.org/kurojebupixopitoka.pdfIn PDF document text
    • http://jedomagisuw.getenjoyment.net/dezezitararog.pdfIn PDF document text
    • http://lelekelosutov.getenjoyment.net/troy_bilt_econo_horse_tiller_for_sale.pdfIn PDF document text
    • http://rolapisi.scienceontheweb.net/where_should_most_of_your_calories_come_from.pdfIn PDF document text
    • http://dajexori.mypressonline.com/whirlpool_washing_machine_repair_service_delhi.pdfIn PDF document text
    • http://soldonlakewood.com/12_apostles_symbolsxjypl.pdfIn PDF document text
    • http://study-english-04.space/1187621583182l8g.pdfIn PDF document text
    • http://bapatavusirave.mygamesonline.org/2012_ktm_350_exc-f_owners_manual.pdfIn PDF document text
    • http://rixorevu.getenjoyment.net/how_to_start_your_own_cake_decorating_business_at_home.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://xurosuforudev.atwebpages.com/gedijomosekoposege.pdfIn PDF document text
    • https://s3.amazonaws.com/sefabe/free_android_emulators_for_pc_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/gedimuta/fivisojamejatozovago.pdfIn PDF document text
    • https://s3.amazonaws.com/paxuvagal/ark_admin_command_metal_tree_platform.pdfIn PDF document text
    • https://s3.amazonaws.com/nuxulikiwab/95426262529.pdfIn PDF document text
    • http://kewevagisugimuw.onlinewebshop.net/c_language_while_loop_multiple_conditions.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eedb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEDB 5576 bytes
SHA-256: 34230f5c790a6abfa3e366fa9fa23e5e35396cb6dabfdeb06503e4e31836e02a
font_01_sfnt_off000101a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A7 11036 bytes
SHA-256: 0e8e45ac9cb39f49d170fd61a521514bd139ac89adab81a362796482cbc2ef9a
font_02_sfnt_off0001273e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273E 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176