Malicious PDF — malware analysis report

Static analysis result for SHA-256 313596ae9230490f…

MALICIOUS

PDF

81.0 KB Created: 2021-03-05 03:09:43 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 8e78b7d909784099158dafb4301a7413 SHA-1: de068ddac2a2b843c55da116560b434d3d220eb5 SHA-256: 313596ae9230490f65da3fafb9afef727909a2651fa94c20e47a90d2d123d9ed
244 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://yafferge.ru/wix?keyword=brown+housing+lottery', likely lead to phishing or malware distribution sites. The ML classifier and ClamAV detection further support its malicious nature, indicating it's likely a phishing or trojan variant.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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 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.
  • 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://yafferge.ru/wix?keyword=brown+housing+lottery In PDF document text
    • http://optalpha.com/sinidaximokewuxavekumazoxkqxbi.pdfIn PDF document text
    • http://yesnutural.space/how_to_edit_blog_on_wixkpzvm.pdfIn PDF document text
    • http://xsafak.com/96129852960hkxm1.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/8ef8fe13-2e5d-4058-adf0-e213e11ab1af/99019938608.pdfIn PDF document text
    • https://13fad4bf-7224-44b3-802b-16842e97d241.filesusr.com/ugd/b14664_53e81e393d6549eea453484ac94568a7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ac5e9e17-c8be-4d5b-a9cb-d6b1f609009b/sixixisirizurelosufi.pdfIn PDF document text
    • https://73f4d879-981c-49fe-abc7-520f36a14a84.filesusr.com/ugd/b77b08_affe1cd10a71494790e87e6f0c6aca76.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nefunupu/68896660577.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/382b7465-96b9-43af-9d1b-dbb128a668dd/mansions_of_madness_storage_solution.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b6afc27-34ff-4e63-883b-6cd3c0562e85/the_master_key_system_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f63c5b1a-0903-46b2-a645-05453e7b550a/lg_fridge_craft_ice_maker_not_working.pdfIn PDF document text
    • https://s3.amazonaws.com/wixatax/aether_catharsis_piano_sheet.pdfIn PDF document text
    • https://s3.amazonaws.com/nefunupu/nikuxogajenuwego.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2981907e-03a8-49e8-8308-c8a99dd247ad/hotpoint_gas_stove_igniter_replacement.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f67de5e7-19a9-410a-9e19-a315e0673d48/fesatemumopesobesijiduxul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/333cbb31-20be-45e7-8b31-a65aaca07d38/lolixenexipi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18f3486c-a6eb-42f9-afa6-63901bdf34c1/garp_frm_exam_dates.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d590fec3-2e5c-49bf-a6eb-af19553db13d/what_is_unity_in_a_painting.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/41959798-7e25-4d7a-a686-b8c85d1031b8/27125713561.pdfIn PDF document text
    • https://8772a198-af03-49ef-8724-5feb7546cb8a.filesusr.com/ugd/436f04_e953fafbeaeb4bc4b93357f7c1cfb63d.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000102c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102C0 4980 bytes
SHA-256: 696a0d9bee2025d0f321afc61efa11d60e2f8e6d209901fa222b49962f577c93
font_01_sfnt_off000113c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113C6 10408 bytes
SHA-256: f4065f944380cdd5e25b5769c07973c31bc8a00c6e5e2b9edd20f4bc2a6a87d0