Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd9e13726c1b5df2…

MALICIOUS

PDF

88.6 KB Created: 2021-05-27 21:51:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: ccbf1fae4af3c4e93f04cb4b28f40c59 SHA-1: 140416a619173b5d18f57d410d904d2116e8d9f5 SHA-256: dd9e13726c1b5df2ff45acb9080cf3aa1469060fa269d65437b619ae4ca859da
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting, indicative of an SEO link farm. The primary URL, 'https://gimoguvi.ru/strik?utm_term=8-4+skills+practice+trigonometry+worksheet+answers', suggests a lure to disguise the malicious intent. ClamAV and ML heuristics confirm its malicious nature, classifying it as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • 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 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.
  • 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://gimoguvi.ru/strik?utm_term=8-4+skills+practice+trigonometry+worksheet+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4444884/normal_60301ed1c0f1b.pdfIn PDF document text
    • https://depuxibuf.weebly.com/uploads/1/3/4/7/134762413/gekoxuvekow-wesemivuwaz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454562/normal_60679c665e287.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420592/normal_601207b2e8419.pdfIn PDF document text
    • https://nigejozezasila.weebly.com/uploads/1/3/4/7/134768622/7771400.pdfIn PDF document text
    • https://newadagunezadev.weebly.com/uploads/1/3/4/6/134684801/3520569.pdfIn PDF document text
    • https://kivobuduzuv.weebly.com/uploads/1/3/0/7/130739084/6132875.pdfIn PDF document text
    • https://bedakowunuva.weebly.com/uploads/1/3/4/3/134342711/zatetokilonujubowe.pdfIn PDF document text
    • https://gefawopunov.weebly.com/uploads/1/3/0/9/130969454/5155555.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477629/normal_6015d69d99532.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420438/normal_5ffe54ed45a86.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473645/normal_60020a34277e9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408875/normal_603b763c07c53.pdfIn PDF document text
    • https://pekosorevonoxa.weebly.com/uploads/1/3/0/7/130739373/soveziwudodete-nepawezobofoz-madovodujonuzef.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416671/normal_5ff107b835e0f.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://uploads.strikinglycdn.com/files/d9129e70-205c-418c-8db4-1b57d92d892e/dagetenupem.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a0e6929-277f-45b5-88bf-ac9ae4766f08/how_to_use_a_slow_cooker_for_pork.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c3526fd0-9623-4806-9862-f5dc844a53ea/64804800752.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a4161f3c-5f49-4d6d-9709-234d4a1ad5b8/wosuwarewovimaninuvozo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d33e768d-1d59-464a-9989-6e850eac6d38/chicago_electric_10_inch_tile_saw_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a1aa5b6-ff89-4e4a-abaa-d98e76228124/dewinilubutopedi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e60acc13-1ca5-4982-ba35-4adf515775ed/taranis_qx7_case.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9f7707c-f339-4534-b9d8-b2f7243b7749/is_the_myer_briggs_test_accurate.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e446a4e6-5c9f-4225-a15d-a3229149ff8c/when_a_man_loves_a_woman_percy_sledge_download.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_off00010c4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C4C 5612 bytes
SHA-256: 065a876587aa91ea453c52738a19d8b2defaa44331d6955f46191afe4411a25b
font_01_sfnt_off00011f43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F43 10876 bytes
SHA-256: ef0c7b7ad334fcaa62c2224c4aa581d9f37cec7cbefd12b12956dacc185d16ce
font_02_sfnt_off0001448a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1448A 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3