Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2044508fa814521…

MALICIOUS

PDF

39.5 KB Created: 2020-08-31 09:46:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb45df5088b623f1f89616c960adb41f SHA-1: fad81342721871e299c5fc2ad204bad58a08ea71 SHA-256: a2044508fa814521f54baf9d36d6cd104186e6c35a719a8cd8b13bdc751e0e88
154 Risk Score

Malware Insights

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

The PDF contains a link farm, with the primary malicious link being a redirector to a URL containing a textbook title, likely a lure for users seeking academic materials. The ML classifier strongly indicated maliciousness, and the PDF structure suggests it's designed to host numerous external links, many pointing to benign Shopify domains, but one critical redirector. No scripts were extracted from this sample.

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.cc/wix?keyword=calculo+de+varias+variables+thomas+11+edicion+solucionario
    • https://cdn.shopify.com/s/files/1/0437/8722/3198/files/45846151417.pdf
    • https://cdn.shopify.com/s/files/1/0432/6601/5396/files/mathematical_induction_examples_and_solutions.pdf
    • https://cdn.shopify.com/s/files/1/0428/4484/8295/files/34671148396.pdf
    • https://cdn.shopify.com/s/files/1/0437/4586/9985/files/53799172791.pdf
    • https://static.usrfiles.com/ugd/38eac1_2fac38d1d6f7411686497ce0b651b458.pdf
    • https://static.usrfiles.com/ugd/b8c837_a980c927bb7c4daf95d55fc2b391a09a.pdf
    • https://static.usrfiles.com/ugd/b8c837_2c4b3a04de30470ea87aeb24f6f73715.pdf
    • https://static.usrfiles.com/ugd/b8c837_b05a48b739514b51a755264b2be66eba.pdf
    • https://static.usrfiles.com/ugd/cf14a4_f04a2784645c4d94bce0afba74412444.pdf
    • https://static.usrfiles.com/ugd/4c76bf_6f69b80e7a41493180921909773c0411.pdf
    • https://cdn.shopify.com/s/files/1/0431/6545/0391/files/72938907946.pdf
    • https://cdn.shopify.com/s/files/1/0431/2956/9434/files/online_extract_rar_file_to.pdf
    • https://cdn.shopify.com/s/files/1/0429/3342/0195/files/7766457635.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004adc.bin
daf6ab21adceb2de7e85df688012183698fb0ef0475447e00fe3dcbc98e0a14c
pdf-font-stream PDF embedded font (sfnt) at offset 0x4ADC 5336 bytes
font_01_sfnt_off00005cdb.bin
49f4c54e40145de258b482eb827399dfe132cbceb4756531fdab37bbbcd7869b
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CDB 11124 bytes
font_02_sfnt_off000080a7.bin
cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34
pdf-font-stream PDF embedded font (sfnt) at offset 0x80A7 4324 bytes