Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9a1125857301a01…

MALICIOUS

PDF

87.3 KB Created: 2021-03-29 18:27:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: ec2e5ad7679647417d5e2f087e3e0250 SHA-1: 98d7dc7e370c949f73033eb20a745c3e6837a03d SHA-256: b9a1125857301a01d2567050abbe039e33c5245aeb83963677665ce34e5e7086
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to other PDF documents, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and numerous external URIs are indicative of a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://seumenha.ru/award?keyword=blastulation+in+amphioxus+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4419818/normal_604e8488055a0.pdfIn PDF document text
    • http://pixunune.sportsontheweb.net/good_quotes_from_alice_in_wonderland.pdfIn PDF document text
    • http://tafugegajotu.mygamesonline.org/art_active_release_technique_reviews.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464871/normal_5fca8f66b96c6.pdfIn PDF document text
    • http://jepenufi.getenjoyment.net/hp_elitebook_6930p_screen_price_in_nigeria.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473044/normal_603c58f2c0477.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419623/normal_5fdd30421599d.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/8d22facc-1420-41ae-b957-d0c117daeffd/29749519584.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4076afda-809e-4336-ba10-17019d698bba/95777557412.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5b46390d-9045-4767-86f2-953990acb9d4/31368175510.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0eb1fffb-088c-450c-b133-d6e3d33d79e1/manual_gps_garmin_nuvi_52_espaol.pdfIn PDF document text
    • https://s3.amazonaws.com/gixawetopoli/crear_una_hoja_de_vida_online.pdfIn PDF document text
    • https://d17f4099-ecc1-42b1-9c73-51521793457c.filesusr.com/ugd/4a2613_43086cc07ff04270b109fbce025c9043.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/790a6c27-01cb-4c02-a909-c82fa93b0d5e/xujofiduro.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f2dfa483-9d3a-492b-941c-e04216c33eb8/jaxabazituniketikedi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6c8924e-e6cd-4a5d-814d-970e9880f821/74006923559.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f123435-f57b-4f92-b464-6aa3619d0116/limove.pdfIn PDF document text
    • https://acfc0e76-311d-46af-9c13-f46c112eb424.filesusr.com/ugd/f90bad_c6e553b354ad4dc2a0eddee8e012b478.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/711ab547-f540-486b-a6bc-3a24dd860279/ds2_ultra_greatsword_moveset.pdfIn PDF document text
    • https://s3.amazonaws.com/fodose/algebra_1_chapter_3_test_answers_pearson.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000119d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D5 5300 bytes
SHA-256: 9e519c05253b3c42577bcc4cacda2cc277903114cafef35496bb9f4640987664
font_01_sfnt_off00012bbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BBF 10740 bytes
SHA-256: 37bdb18ef532de30a199ab5275cba6b9cec5b8be1409e45308b74f9e548670a0