Malicious PDF — malware analysis report

Static analysis result for SHA-256 84404b6df64328c1…

MALICIOUS

PDF

41.9 KB Created: 2020-08-12 06:22:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e89dfb311d44fe6689a24995680257af SHA-1: ec2fe50ea25d8100d6f6b19d86cb9fa1bedbb881 SHA-256: 84404b6df64328c123113c39cdf0a0cee1e7fcce420fc7f1adef6683a0f7af9b
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external PDF files hosted on various domains. One URL, 'https://ttraff.ru/pify?keyword=psychiatry+cases+for+medical+students+pdf', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains similar URLs and appears to be a lure for academic content, likely to disguise malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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.ru/pify?keyword=psychiatry+cases+for+medical+students+pdf
    • http://rejop.ssppilechina.com/uploads/1/3/0/7/130738969/c9ace6c74.pdf
    • http://files.desmoinesmennonite.org/uploads/1/3/0/7/130775588/5ef55f9378ad429.pdf
    • http://files.jescaprudencio.com/uploads/1/3/1/8/131871501/laxosamapuzomu_xoxegetuteri.pdf
    • http://zoridogag.wucoathletics.com/uploads/1/3/0/7/130776783/2271873.pdf
    • http://files.eremiticservants.org/uploads/1/3/1/6/131637273/8295656.pdf
    • https://cdn.shopify.com/s/files/1/0436/6693/1862/files/savimefiwuvorefadurewepa.pdf
    • https://cdn.shopify.com/s/files/1/0452/7492/3169/files/kavarupifalebamufazev.pdf
    • https://cdn.shopify.com/s/files/1/0435/3405/7621/files/essential_university_physics.pdf
    • https://cdn.shopify.com/s/files/1/0431/3756/4823/files/ranob.pdf
    • https://cdn.shopify.com/s/files/1/0430/8900/2650/files/51835532509.pdf
    • https://cdn.shopify.com/s/files/1/0428/3331/3958/files/livro_balstica_forense.pdf
    • https://cdn.shopify.com/s/files/1/0428/6427/9718/files/korean_visa_application_form_editable.pdf
    • https://cdn.shopify.com/s/files/1/0428/2934/9030/files/tujavudunafava.pdf
    • https://cdn.shopify.com/s/files/1/0431/9212/3553/files/11357458518.pdf
    • https://cdn.shopify.com/s/files/1/0431/0699/2289/files/what_is_centrifugal_casting.pdf
    • https://cdn.shopify.com/s/files/1/0430/4338/9597/files/87965786110.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000641b.bin
637b7add0f309cba7b2fe1415dc1440363a6d1f2be45a656ac5b3844514e98a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x641B 5496 bytes
font_01_sfnt_off000076a9.bin
391ff8729ccfd69ec5115f9e32c7634aa1f83b10600a28b66f07b51ea08b9c1c
pdf-font-stream PDF embedded font (sfnt) at offset 0x76A9 10524 bytes