Malicious PDF — malware analysis report

Static analysis result for SHA-256 34c3b3682502db3a…

MALICIOUS

PDF

43.8 KB Created: 2020-08-31 20:44:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d024e6f14d5eb19457aab94189d323a7 SHA-1: 79d5cb8b1362789cad1c891a3600ee1e3aad02d5 SHA-256: 34c3b3682502db3a9e053375cf5762b7ab76a41edc40ab74ee377a97a1e1ff66
152 Risk Score

Malware Insights

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

The PDF contains a malicious redirector link disguised as 'aptitude questions pdf for gate', which is a common lure for phishing or malware delivery. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK confirms this, and PDF_SEO_LINK_FARM indicates a large number of embedded links, likely to obscure the malicious intent and distribute traffic. The ML classifier also strongly indicated maliciousness.

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/wix?keyword=aptitude+questions+pdf+for+gate
    • https://cdn.shopify.com/s/files/1/0431/6279/6186/files/ielts_reading_recent_actual_test_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0433/3453/3275/files/8259306001.pdf
    • https://cdn.shopify.com/s/files/1/0437/8198/0321/files/behold_the_lamb_of_god_chords.pdf
    • https://cdn.shopify.com/s/files/1/0433/2421/1354/files/38525690491.pdf
    • https://cdn.shopify.com/s/files/1/0429/4384/0412/files/abscesso_pulmonar.pdf
    • https://static.usrfiles.com/ugd/b8c837_910e7a75e1584e87aaf707987ae68d13.pdf
    • https://static.usrfiles.com/ugd/0cd3a8_fdce45783dfa4b68aa3ad099c95455cb.pdf
    • https://static.usrfiles.com/ugd/b8c837_f375dc56705d43878a738153c5c58be1.pdf
    • https://cdn.shopify.com/s/files/1/0429/3433/7695/files/33432319141.pdf
    • https://cdn.shopify.com/s/files/1/0437/8856/6677/files/lupowesuzoriwaledukonova.pdf
    • https://cdn.shopify.com/s/files/1/0433/0268/2789/files/fumela.pdf
    • https://static.usrfiles.com/ugd/2d1648_534c9bef66a7473a92487956e02bc513.pdf
    • https://static.usrfiles.com/ugd/b11f6d_f9d5146d6c9349f7918dd3bdd45f93e7.pdf
    • https://static.usrfiles.com/ugd/90423f_68bcc76c5aea48bbb0cff948935fe577.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_off00006a01.bin
62ca136a5f7665374d13f2ce570b75ec1d4e8c4bd942f5277f484ba80d05f192
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A01 5292 bytes
font_01_sfnt_off00007c0d.bin
f67a68b3f81a55ba48e3aa70a989da54dffdac65ebc3b2661a3f70381cf82e30
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C0D 12116 bytes