Malicious PDF — malware analysis report

Static analysis result for SHA-256 905ec443f1aae4fa…

MALICIOUS

PDF

74.2 KB Created: 2020-11-18 07:43:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: baad5ad03f2772c62b2b3740685096ce SHA-1: e055cb8b82ec15cdb4f7aea895406a51ff789aec SHA-256: 905ec443f1aae4fa2467f5b156d10080bf9f5471c3601e8983a5ba5ab684cc77
314 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded links that redirect to known malicious infrastructure, specifically designed for credential phishing, impersonating the Amazon brand. Heuristics indicate it's a redirector link and a brand credential phishing lure. The ML classifier also strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the nature of the embedded links and the phishing lure suggest an intent to download and execute a second-stage payload or directly lead to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://rovivivaju.weebly.com/uploads/1/3/4/3/134313680/pupazopin-tufuredes-napofowan.pdf.
  • 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://ggtraff.ru/aws?utm_term=freelance+graphic+designer+invoice+template In PDF document text
    • https://cdn-cms.f-static.net/uploads/4375088/normal_5f94ae08f01ab.pdfIn PDF document text
    • https://rovivivaju.weebly.com/uploads/1/3/4/3/134313680/pupazopin-tufuredes-napofowan.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374362/normal_5f8e8e53a63c4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423452/normal_5f994c474d4bb.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/2c62282f-2a72-4ee0-b90c-90dda63038a5/33203466844.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e478a0fe-2d7e-46f4-ba3d-da45d3aaeee4/14845533961.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/abf5e508-10b0-4786-91b9-31ffce8b0a58/54159902308.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5caeaa01-e431-4ce1-9b3a-e30d9e67d935/4605497553.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/78364a49-595f-401b-8f3a-d8f4b52ba8cc/68008817104.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77a5bf4d-4e05-4321-9282-b427f7c4c717/jubezotomajobitafu.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_off0000e4c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4C2 5500 bytes
SHA-256: 938b3491a868c33e46f8f8f95b82080f9e5b631adbf8f896b1d252fb728bdd07
font_01_sfnt_off0000f75b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75B 10704 bytes
SHA-256: 44838a3fa0c49cba67f72dd47dc9d2eacb75f8b1ff78b88e819907aedb50eb23