Malicious PDF — malware analysis report

Static analysis result for SHA-256 1fb7363991cbdcb8…

MALICIOUS

PDF

75.3 KB Created: 2021-04-05 19:33:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 5f9109b6f8349d349e2e89c0cb2444a7 SHA-1: cf704d30012bc6a05c789c1f2325c3d4ea7d1c79 SHA-256: 1fb7363991cbdcb816554dca051c5d64b48684ae1d06ddae57389d9b80707203
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://golowaki.ru/award?keyword=cursive+alphabet+chart+pdf PDF link annotation
    • http://mjawebdesign.net/12465710371t3mtt.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482018/normal_60097b40e66a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379744/normal_6028667d12ffc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382790/normal_601976cd3c3c5.pdfIn PDF document text
    • http://carbackseat.site/acids_and_bases_neutralization_reactions_worksheetj2ckv.pdfIn PDF document text
    • https://joletumutete.weebly.com/uploads/1/3/4/8/134871701/webomikitureses-naluzoxufe.pdfIn PDF document text
    • http://jilet2.club/tanuwegedevukuwp9ev1.pdfIn PDF document text
    • http://x-bionic.shop/what_is_the_best_graco_pack_n_play_with_bassinetlfdi4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499317/normal_5fe999e79284c.pdfIn PDF document text
    • https://revijokatise.weebly.com/uploads/1/3/3/9/133999222/8224685.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.opentle.orgIn PDF document text
    • https://uploads.strikinglycdn.com/files/492ea973-69c1-4cca-b3dd-e9b2cca9289b/romatimizijakozuj.pdfIn PDF document text
    • https://14579757-8399-40ae-9aa0-1c510f02119b.filesusr.com/ugd/5613ee_40c819b47ea84cc5a43986d460f27b1b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f8bf521-53fb-4813-ad3a-af1d476eb9e4/77535592713.pdfIn PDF document text
    • https://50b44c92-959e-4a15-bf83-93d6b2b518d6.filesusr.com/ugd/3ed44c_a3a3bbf8afea493dad61258b408907c6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/54fe87ef-bda2-43e2-9865-bd14bfd943c9/how_to_apply_for_food_stamps_in_el_paso_tx.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f06de474-052a-4845-8e4a-3c80e28ecb7c/10743921140.pdfIn PDF document text
    • https://994180ce-385f-4272-9833-4a204a825e0f.filesusr.com/ugd/ec0c41_acaea1ebb24a4b89a1880d0ee5cb7114.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b83ebcc0-5384-46ce-9161-cf1070d4680c/2363011584.pdfIn PDF document text
    • https://86a9da1b-0b57-4b35-a77a-523886b904cd.filesusr.com/ugd/0d9a50_47d0779845da4b52beee1d86ff1d20be.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ad01ff7-a6ff-4449-a0f3-8649e4e7ce08/what_is_social_darwinism_theory.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e705aa18-2b16-4e9d-8412-51053dbe0ce4/rukejo.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
    • http://www.gnu.org/licenses/gpl.htmlIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD482 5348 bytes
SHA-256: 5420a25870efd74405655c43bc98cc5d99b773483a530d8400478a6c64850b0d
font_01_sfnt_off0000e69b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE69B 7972 bytes
SHA-256: 2fdeb9b2784735f723e5f968c78cb57900cbeabea1a75f17b5bee6f9ca181b5e
font_02_sfnt_off0000fc47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC47 10276 bytes
SHA-256: e5e55c8d650e1792248c9c33b004dc80e6f1b727207933ef24999fb800279878