Malicious PDF — malware analysis report

Static analysis result for SHA-256 1140b090a42050f7…

MALICIOUS

PDF

82.2 KB Created: 2021-05-07 19:53:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 8bf0d606000eb1e1cb6f49075dce832d SHA-1: b5be86a9d8133acb1a09456da3d28ed96a134659 SHA-256: 1140b090a42050f705ba1fb81b0058aa9c50d2ff9019599bda284615ab257ab1
254 Risk Score

Malware Insights

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

This PDF file contains numerous embedded links, with a critical heuristic firing indicating it redirects to known malicious infrastructure. The document body, though heavily obfuscated, contains text related to a '9.9 scatter plot worksheet answer key', suggesting a lure to trick users into clicking the malicious links. The primary malicious URL identified is https://yafferge.ru/strik?utm_term=9.9+scatter+plot+worksheet+answer+key, which is likely used for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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
  • 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://yafferge.ru/strik?utm_term=9.9+scatter+plot+worksheet+answer+key In PDF document text
    • https://cdn-cms.f-static.net/uploads/4444386/normal_60288e512af89.pdfIn PDF document text
    • https://zatikavetix.weebly.com/uploads/1/3/2/3/132303242/sivutudeva-pebibejese-wosizuruk-tigumixibi.pdfIn PDF document text
    • https://muxasikij.weebly.com/uploads/1/3/1/8/131872285/mirazika.pdfIn PDF document text
    • http://tokio-2020.fun/wosomop93f81.pdfIn PDF document text
    • https://xizadububexo.weebly.com/uploads/1/3/4/5/134595199/ninifijisutuf-zevapuluvagabo-dopufa-tefopezef.pdfIn PDF document text
    • https://motovonesavot.weebly.com/uploads/1/3/4/6/134690882/4304605.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416512/normal_603570f78edfe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385648/normal_600dbb3342c80.pdfIn PDF document text
    • http://marketitaly.info/lutefagowuxisevy5jyl.pdfIn PDF document text
    • https://xowavexinoj.weebly.com/uploads/1/3/1/4/131408618/8861404.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445119/normal_5fe9f48d2beeb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393772/normal_6036b664e0388.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://s3.amazonaws.com/xonaxevetaf/bewakatazinatidaladonug.pdfIn PDF document text
    • https://s3.amazonaws.com/kovibu/how_to_protect_code_from_reverse_engineering.pdfIn PDF document text
    • https://64b67c6e-fbbd-4787-add8-9ed3e274c95c.filesusr.com/ugd/eb6612_fdbeede3863c46029241521647cc1296.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fizaxo/writing_academic_essay_guideline.pdfIn PDF document text
    • https://s3.amazonaws.com/moduluzuxikari/brainpop_cellular_respiration_quiz_answers.pdfIn PDF document text
    • https://d8d691c7-cf48-432b-bece-a54604b57851.filesusr.com/ugd/1e3a4b_529d3bcf6ca6486dafa825e68435ca01.pdf?index=trueIn PDF document text
    • https://288c7b4b-0494-48f6-8ee2-9dd519b96b0a.filesusr.com/ugd/a107db_fef204fbaed14d9ea87bb1d7409a4493.pdf?index=trueIn PDF document text
    • https://2dc0326d-ac60-47d8-bf46-f2dc9d334570.filesusr.com/ugd/21b4a7_5f5064bdbf3040038fb990865fbf14f6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/muvojugejoxip/intermatic_ej351_timer.pdfIn PDF document text
    • https://s3.amazonaws.com/gatazeromij/lowedexinaw.pdfIn PDF document text
    • https://s3.amazonaws.com/padanivozeb/kigujeluxowokimabetisoxu.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_off0000f860.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF860 5112 bytes
SHA-256: 91c2c5c6145d71eee82f963573deae21ee2fdf103832eb75c6e1856cacdac14b
font_01_sfnt_off000109c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C1 10364 bytes
SHA-256: 2fb34b62175538cb597acbcbc2cd0e955f2efdd4785400dba0b9a0926e56aa57
font_02_sfnt_off00012d06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D06 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333