Malicious PDF — malware analysis report

Static analysis result for SHA-256 21ebf9c5b6cf600e…

MALICIOUS

PDF

117.9 KB Created: 2021-05-11 14:33:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8e6d2017b1419a2bb9557bbcb305e39e SHA-1: 7e833fb14f8ccc252b0b51aec56f6555e69d9f66 SHA-256: 21ebf9c5b6cf600e895e079fa042c3483d8a585a4afea0fe046df8d74c001d07
186 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, many pointing to disposable hosting, indicating a link farm or phishing attempt. ClamAV and ML classifiers strongly flagged this file as malicious, specifically as a phishing trojan. The embedded URLs, such as 'https://kuzutuzo.ru/strik?utm_term=tav+prasad+savaiye+deenan+ki', are likely part of the malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/strik?utm_term=tav+prasad+savaiye+deenan+ki
    • http://jobware.pro/washington_wizards_nba_scoreboardo9me0.pdf
    • http://robugipunebib.mygamesonline.org/62754769451.pdf
    • http://harkateine.fun/vevabixo92lh7.pdf
    • https://cdn.sqhk.co/gaxumisi/QhdSJGW/uk_malaria_treatment_guidelines_2017.pdf
    • https://cdn.sqhk.co/besawevij/bbPhaxb/children_s_beds_for_sale_johannesburg.pdf
    • https://cdn.sqhk.co/rarukaboz/jhcgiPT/45091226411.pdf
    • http://carluxepaint.site/monitoring_internet_activity_at_workw49c6.pdf
    • http://wajofima.mywebcommunity.org/53764319415.pdf
    • http://medicinfo.online/what_does_it_mean_if_your_dog_is_thirstyirpxj.pdf
    • http://mitedujonajezed.scienceontheweb.net/sawikozufizabezajateli.pdf
    • https://cdn.sqhk.co/libobivole/dhb6Xgg/i_am_death_gif.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://fedorahosted.org/lohit
    • http://www.daltonmaag.com/
    • https://4f870d4f-701c-4ec6-bbb3-7277acc5528a.filesusr.com/ugd/fdcb8d_21e60f5233f74156a1c887ecf277eae6.pdf?index=true
    • https://71f68c9c-1037-483c-a0ca-f268b7ddd3c8.filesusr.com/ugd/87fdc7_4226d9676cc948688c26cee9cebc174c.pdf?index=true
    • https://uploads.strikinglycdn.com/files/294ed6cc-e2a0-4f7c-9b45-9c80956006ff/new_moon_in_capricorn_2021_time_and_date.pdf
    • https://uploads.strikinglycdn.com/files/b983a81a-165f-4f9c-b1d5-0a35893bdaa5/mesine.pdf
    • https://3df06c22-1e8a-4082-8cc2-a0fdc0609706.filesusr.com/ugd/d86e81_137ae6985ea94b479bb77e438e9638a7.pdf?index=true
    • https://e905a76e-7bc1-418c-be29-e8eda1603e86.filesusr.com/ugd/3fb32a_3bc78c853e0d451f96ff2df69b43e229.pdf?index=true
    • https://6f81cef9-66a2-447d-9e1d-4c0427ef15c5.filesusr.com/ugd/4d935e_bad238c56b2d40a1a604b967cbc42820.pdf?index=true
    • https://uploads.strikinglycdn.com/files/45b3e818-9c8c-4980-a495-38f6169d3d3e/62730740807.pdf
    • https://44407f20-7244-4107-9544-84d8151b6f9a.filesusr.com/ugd/8508de_5ec8ca2f1ac446fbbb7d7f8f180bada0.pdf?index=true
    • 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/
    • http://scripts.sil.org/OFL
    • http://www.geocities.com/mitra_anirban/hobbies.htmGNU
    • http://www.gnu.org/copyleft/gpl.htmRegular
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 6

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013f41.bin
17bd61cb95c0c62a1ef08e88d17a52666c66b5def4b14c0d49a470920c0827a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F41 4696 bytes
font_01_sfnt_off00014f39.bin
240b01ea4caa45f57f54ab4d6d5eb6187b906162b2682bc4dcfb9155b206388d
pdf-font-stream PDF embedded font (sfnt) at offset 0x14F39 3772 bytes
font_02_sfnt_off00015adf.bin
1ba5adf5e7ef58777270f4742ffabd6085af1c482d8f9d4a4ccf125b3670e77e
pdf-font-stream PDF embedded font (sfnt) at offset 0x15ADF 12944 bytes
font_03_sfnt_off0001813b.bin
cf01c79162087acd870092246e56402999374facdbdb05370075122dcdb7ffb9
pdf-font-stream PDF embedded font (sfnt) at offset 0x1813B 10836 bytes
font_04_sfnt_off0001a668.bin
8f0e4cc40e189f844ba505870c5743bf61ee9cdf6cb8b14e370866b3c0b868e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A668 16196 bytes
font_05_sfnt_off0001bb82.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1BB82 4324 bytes