Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f6cc8837e2a0a9…

MALICIOUS

PDF

52.4 KB Created: 2020-07-10 09:02:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-07
MD5: a357f4fc6e68c6cd64962c99aace1869 SHA-1: 32c976f931d865585db91869484d25d1bfe808de SHA-256: 28f6cc8837e2a0a91ae4eb3281c581300fdd13940eb55bb13b0045ca15ac04dd
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded links, many of which point to link farms designed for SEO manipulation. One prominent link redirects to `ttraff.com`, a known malicious redirector. The document body, though partially corrupted, suggests a lure related to 'Ban dihydrogen monoxide worksheet answers', indicating a social engineering attempt to entice users to click the malicious links. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • 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.
  • 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://ttraff.com/wb?keyword=ban%20dihydrogen%20monoxide%20worksheet%20answers In PDF document text
    • http://files.wao-lb.com/uploads/1/3/1/6/131607575/rasevamuka.pdfIn PDF document text
    • http://files.neksscottishrite.com/uploads/1/3/1/0/131071056/2c1e2872c.pdfIn PDF document text
    • http://files.andreanelson.studio/uploads/1/3/1/8/131871690/b02bc.pdfIn PDF document text
    • http://files.nejnamc.org/uploads/1/3/1/6/131607346/bujowadatasivo.pdfIn PDF document text
    • http://files.classicbirdhunts.com/uploads/1/3/1/3/131382447/vunorameweba_lurawanewasikip.pdfIn PDF document text
    • http://files.dynamicathleticcenter.org/uploads/1/3/0/7/130740050/41679e42.pdfIn PDF document text
    • http://files.customerservicetalk.com/uploads/1/3/1/6/131607733/wolibufabixidu.pdfIn PDF document text
    • http://files.lovingthemother.com/uploads/1/3/0/7/130775292/4944382.pdfIn PDF document text
    • http://files.inafip.org/uploads/1/3/1/0/131070895/9a3f3b.pdfIn PDF document text
    • http://files.balatonumc.org/uploads/1/3/2/6/132696330/xunivixojujesakas.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://walixamitava.files.wordpress.com/2020/06/vizalowanedegi.pdfIn PDF document text
    • https://kuvilagegap.files.wordpress.com/2020/07/86749911973.pdfIn PDF document text
    • https://zojaxatij.files.wordpress.com/2020/06/wezilofurolo.pdfIn PDF document text
    • https://bajajajusiro.files.wordpress.com/2020/06/renom.pdfIn PDF document text
    • https://pateviwa.files.wordpress.com/2020/07/puzamegolutorodafaxiri.pdfIn PDF document text
    • https://buluzoti.files.wordpress.com/2020/06/53882017735.pdfIn PDF document text
    • https://noxogiluvu.files.wordpress.com/2020/06/zugigogaxipumirebiwode.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/gokibaleginasesomedusuj.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/fulefevizurosojasi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tivaluzisezulumavolo.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_off00007e13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7E13 5368 bytes
SHA-256: ad9ebc9fd0693594c9541e7af748a15ddf094066301546ca2270d406f4d5844f
font_01_sfnt_off00009045.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9045 23480 bytes
SHA-256: 0b41937cb2085bea8b45ce2bb16a0fd59f4da233a06cfa82b7d123be2de1d362