Malicious PDF — malware analysis report

Static analysis result for SHA-256 55673d32cf9bb48f…

MALICIOUS

PDF

79.4 KB Created: 2021-05-19 08:19:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 27f023db0e2a18624b706ea1b4716021 SHA-1: e455f554825874ae6d92059f1b5af8cf120bd6da SHA-256: 55673d32cf9bb48fbe204659a3df723774a77af469716c640d9827a3b3015220
214 Risk Score

Malware Insights

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

The sample is a PDF document flagged by multiple critical heuristics as malicious, including a redirector link and a link farm. The embedded links, such as 'https://dafemum.ru/strik?utm_term=carl+flesch+scale+system+pdf+cello', strongly suggest a phishing or malware distribution attempt. Although no scripts were explicitly extracted, the PDF structure and link farm indicate an intent to redirect users to malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://dafemum.ru/strik?utm_term=carl+flesch+scale+system+pdf+cello In PDF document text
    • https://static.s123-cdn-static.com/uploads/4501046/normal_5ff4bcfbdb8ce.pdfIn PDF document text
    • https://nuzojumikosa.weebly.com/uploads/1/3/0/8/130814298/488575.pdfIn PDF document text
    • https://verijijul.weebly.com/uploads/1/3/4/8/134861220/gevepukoxizigomaluf.pdfIn PDF document text
    • https://kurajefofukagi.weebly.com/uploads/1/3/4/8/134895289/laxutagufopas.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383695/normal_5ff3b2d6738b0.pdfIn PDF document text
    • https://pewituzusab.weebly.com/uploads/1/3/0/8/130874049/susuketalujove-wusoxo-nidimuvexolewa-pafimawo.pdfIn PDF document text
    • https://sixapinipuso.weebly.com/uploads/1/3/1/3/131384402/fd589f00bdbc4b7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4414849/normal_5ff8af57f1f3b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421205/normal_603326bd222bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449184/normal_5fd9c7d9aa1d4.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
    • https://s3.amazonaws.com/memexelu/grohe_kitchen_faucet_leaking.pdfIn PDF document text
    • https://s3.amazonaws.com/kozewuposoridil/hermes_scarf_size_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/592a02bf-91aa-42d8-a6b0-a1d65ef786e2/how_to_replace_a_lid_lock_switch_on_whirlpool_washer.pdfIn PDF document text
    • http://kivunakoxowufaf.epizy.com/escala_de_alvarado_apendicitis.pdfIn PDF document text
    • https://s3.amazonaws.com/neporezofov/29830155191.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6e3d4a2b-0301-46a7-85a8-c6b44d845d6a/13253247378.pdfIn PDF document text
    • http://fefipunoz.rf.gd/who_triggered_the_asian_financial_crisis.pdfIn PDF document text
    • http://mamawelujuke.rf.gd/konibulirozefozuta.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7915ccf4-afde-4eae-81e2-085708f89c33/plantronics_co52_reset.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/670c5319-48f0-458e-b9a9-73b5591b83eb/best_business_analytics_courses_in_india_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/rufonali/para_que_sirve_el_te_de_canela_jengibre_y_curcuma.pdfIn PDF document text
    • https://s3.amazonaws.com/sinamozagemoger/cyberpunk_2077_weapon_mods_not_working.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d58c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58C 6340 bytes
SHA-256: 643f3a447ae4b9d2834b4bbc6fd879b4b66c2233031050d90c2b8c0a47bab5f9
font_01_sfnt_off0000eaed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAED 5152 bytes
SHA-256: 0d3921bc54810a52223de17082429e04edd6ca828d6025fff7ceadfd9a5afaa3
font_02_sfnt_off0000fc87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC87 11016 bytes
SHA-256: 1dd7556a2852ed1718fa05ab72faa24d23581f6186753416931e41b470f55c2a
font_03_sfnt_off000121d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121D3 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333