Malicious PDF — malware analysis report

Static analysis result for SHA-256 31da66d1496fb6dc…

MALICIOUS

PDF

85.5 KB Created: 2021-03-14 05:31:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 1553f2af7a2e606e44a0c3879f7ef121 SHA-1: b1c9c1eb4b0aea3c16b5b1597aeef562a468e698 SHA-256: 31da66d1496fb6dc0cb8eadb2f9b7374a05b200c3a7f6d602263881ae0dbaee2
186 Risk Score
Tags
free-cdn-ebook-manual-lure

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting services, indicative of a link farm or phishing operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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://golowaki.ru/award?keyword=learn+music+theory+piano+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4402478/normal_6021c050869ff.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427820/normal_601f02df86744.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466146/normal_5fc6029fd017f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453900/normal_5fe0ea5f0dca5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385197/normal_5fd170399bbde.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427795/normal_6004d3e6c3500.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378405/normal_600af05505bc6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e1ca4115-fb55-43f9-84f1-eaf814f8c83f.filesusr.com/ugd/18122d_f20972d0913b46c78a8fe111fa29c6ab.pdf?index=trueIn PDF document text
    • https://ba30dffa-51fe-4caa-9472-6f142403a9bb.filesusr.com/ugd/c2007e_3487726b09ee44d6abc75a2de11636dd.pdf?index=trueIn PDF document text
    • https://849cba27-c1c2-4801-a47f-514a08c45c3c.filesusr.com/ugd/7f7a2c_94a8da658b0c49b891c0a31cfc65a05d.pdf?index=trueIn PDF document text
    • https://68420551-d949-41c4-975b-2ae86aa6d062.filesusr.com/ugd/09c3c7_a0bc5a01a0534e328eab40d1e65791c0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/50ba15e1-1d5f-414d-81bf-fe6eae014a19/9164575490.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/14f671b5-6438-4839-8809-29462e77d710/72711904113.pdfIn PDF document text
    • https://9462281c-6212-45c1-8f90-c4e3c363a226.filesusr.com/ugd/007d40_07e8d6cfef23491cbfaa1d18adb8def9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/542c0b27-1c3b-43fe-9a09-a1a0d05cfb2c/luzamawobojidep.pdfIn PDF document text
    • https://b3df6b87-ca8d-4c26-b815-8c697753997b.filesusr.com/ugd/896a32_8792bf0fa5bc4804acfc1fac9ca3459e.pdf?index=trueIn PDF document text
    • https://899154e9-876a-4ab4-94d5-c8ef2aed10f2.filesusr.com/ugd/dcf9ad_c4061a8217a3441aa65ec20d329e9548.pdf?index=trueIn PDF document text
    • https://c1bbde11-5cda-4f7c-8b74-b2fe90b484f5.filesusr.com/ugd/1c8c6c_3f74e0edacd047adad58be64dfdbd0c2.pdf?index=trueIn PDF document text
    • https://2ffa788b-df2f-461f-b9c5-573bec542745.filesusr.com/ugd/374ce0_986269c9eb9d491db0e8988ae4ab02c7.pdf?index=trueIn PDF document text
    • https://ba789de2-c385-43ee-b32d-a34c698d1993.filesusr.com/ugd/b7082a_8571fe70f6514e4e883a30edc26b3ce6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5315c0f9-0e8f-4615-a13d-da62e9a4d060/dd_5e_forgotten_realms_races.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b5b3946-454a-4a5d-8284-86f75cc0e370/49086226153.pdfIn PDF document text
    • https://9387bd13-3746-4408-b474-2867f26e464d.filesusr.com/ugd/ace02d_c13fd09053a24f5eb4bc913c19eb0c72.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_off00010f24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F24 5408 bytes
SHA-256: b28e4708a35031d0195f010aed67071a6ad11ce0a437b4e892047b9e7567ce73
font_01_sfnt_off0001216e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1216E 11580 bytes
SHA-256: 3820e5fb8aebfa6d721d739c40d8b49c097555fddc3dffd093ce9416a33b2fa2

Open this report in the interactive analyzer, or submit your own file for analysis.