Malicious PDF — malware analysis report

Static analysis result for SHA-256 413a7e870fb7cd93…

MALICIOUS

PDF

88.9 KB Created: 2021-05-24 01:03:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 557691271f2c844b8d7dbd5c88d4d514 SHA-1: 68028365a385095306599666adf748eaefa01667 SHA-256: 413a7e870fb7cd93bdc565f3618bd090dcdc1b3b01139070b515374b5b4327bc
254 Risk Score

Malware Insights

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

This PDF file is identified as malicious by multiple heuristics and a machine learning classifier, including critical alerts for malicious redirector links and SEO link farming. The document body, though obfuscated, contains text related to 'organic chemistry a short course 13th edition free download', suggesting a lure. The primary malicious IOC is the redirector URL, which is designed to lead users to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://dafemum.ru/strik?utm_term=organic+chemistry+a+short+course+13th+edition+free+download In PDF document text
    • https://jasasenud.weebly.com/uploads/1/3/4/1/134131975/puresiridi_nudazuzijazu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491437/normal_5fe77b3bcd4ad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386834/normal_603b18ab289da.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380237/normal_6042d3f9bf300.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497650/normal_6029e796367f4.pdfIn PDF document text
    • https://mivojunap.weebly.com/uploads/1/3/4/7/134720575/doduf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371790/normal_6002d2bd86212.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473926/normal_5ff4b341b5509.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4476595/normal_5fe118e6525c4.pdfIn PDF document text
    • https://bakemelufipunuj.weebly.com/uploads/1/3/4/8/134888112/suluxiko-kapuruxo-pekixoludazilij-nuvuxusus.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425913/normal_6039ab37ce365.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453914/normal_6011c5ad8bb41.pdfIn PDF document text
    • https://dedorewesapizeb.weebly.com/uploads/1/3/4/2/134265869/1e22ee16e4.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/0884aae6-c8bf-4c69-9a47-9f7cdcad288a/how_long_to_get_drivers_license_in_mail_ca.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6fb5dbb2-1a9e-4054-bd16-dd32abbce26d/how_do_you_set_a_casio_2747_watch.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/014a36c0-a7c3-4af5-831f-c6d8a7ae3f7c/giwuwal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2eed983a-f8c6-45af-ba25-e643167c54d2/how_to_read_dna_sequencing_results.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3e97e1c1-9135-4eac-9d1c-7dad604da655/fantastic_beasts_and_where_to_find_them_2016_sinhala_sub_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dd8475c1-e29a-49a7-928c-256057ceea1e/88078755264.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b65f1cc5-2346-467b-87b6-f581c961ef71/xuwazinirijiwisov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b939db72-b892-492b-8cfb-beb8b11f9eb0/wojewiwut.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_off00010e11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E11 5752 bytes
SHA-256: c4fbb3609c9cd721be3207570cb990d495419f71c86eb5e376fb482db4823bc2
font_01_sfnt_off00012192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12192 11156 bytes
SHA-256: 82fdd3f3ecbe0dcc46a3c561693758a4fc431883110c703d5d64f02451d8f9e9
font_02_sfnt_off00014717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14717 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c