Malicious PDF — malware analysis report

Static analysis result for SHA-256 b023aaeb9100768a…

MALICIOUS

PDF

86.3 KB Created: 2021-06-08 21:00:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 141e4b186d1fcaec1054895c4c74e18f SHA-1: 35729174019994a4668ab5e89aa9c61d23b0ad2e SHA-256: b023aaeb9100768a957f51b2f5615a0493c6955d2340568b585b00cc8712a4d4
126 Risk Score

Malware Insights

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

The PDF file contains a heuristic indicating it's a link farm on disposable hosting, directing users to a suspicious URL. ClamAV and ML classifiers also flagged it as malicious, specifically as a phishing trojan. The embedded URL, https://nomylo.ru/pbw?utm_term=surah+yaseen+audio+free+download, is the primary indicator of malicious intent, likely serving as a lure for further malicious activity.

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
  • 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://nomylo.ru/pbw?utm_term=surah+yaseen+audio+free+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4482216/normal_6035aa80d8534.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374178/normal_604206352e3a9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376127/normal_602061d75c8ec.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/d29911ec-5bc9-4a7b-9d4f-da416080088e/1806625688.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/37429df0-7419-405f-b912-9ee9ff3a6e20/how_much_does_it_cost_to_rent_a_carpet_cleaner_from_kroger.pdfIn PDF document text
    • http://varulemenel.pbworks.com/f/download_lagu_sonia_mp3_luruh_cintaku.pdfIn PDF document text
    • http://wiliser.pbworks.com/w/file/fetch/144465165/ba_first_year_sociology_notes_in_kannada.pdfIn PDF document text
    • http://giwupiraride.pbworks.com/f/9963819209.pdfIn PDF document text
    • http://mukonisu.pbworks.com/f/16173391543.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/655100be-7387-4e61-a5ae-69e91a969fdf/zekedufomaf.pdfIn PDF document text
    • http://garifukedako.pbworks.com/w/file/fetch/144843930/88073448839.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ab7890a8-af4c-4359-bca1-e416fc2d98c2/razovagilemiwetaxabixo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/269366fe-7d8d-40df-be59-df387c6b458f/present_perfect_tense_rewrite_exercises.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd7c7a1c-af1f-4f98-9e79-c3daf07c382f/ponurizejitixuwesupurat.pdfIn PDF document text
    • http://natofuke.pbworks.com/f/24350341974.pdfIn PDF document text
    • http://kivupored.pbworks.com/f/public_speaking_activities_for_adults.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/042fbb60-4776-4c66-a62c-56b8967b2250/70971174600.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd2aeedb-d132-4ecd-aebb-82ef97cd00e0/addition_and_subtraction_of_fractions_examples.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/25fdd4fd-08bd-41b0-a70c-ca3a6f3e0cd9/extended_metaphor_meaning_and_examples.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b796791-dc13-412a-8b64-4d5fd715ccfb/wewoxu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2882ff1c-9479-40ca-9029-c25835c05423/37153806369.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16d9c46c-1e87-48ea-977d-f99d300553ab/romotifepex.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_off0000f781.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF781 5292 bytes
SHA-256: 3b61a51b1f6ba7729a445a5e43f43d4ef4cdf0398e6d4141aa9207942569c0cf
font_01_sfnt_off00010991.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10991 11912 bytes
SHA-256: bd4e09a693d2010666d226fc9a3334d7ab04c4f4667edee072baf1ba724c9ddf
font_02_sfnt_off000131f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F5 17284 bytes
SHA-256: e1e263d74ddf2818f411364c35050363ac99991d92effe664ee13ed49004953c