Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c540741382f140f…

MALICIOUS

PDF

84.1 KB Created: 2021-03-29 04:16:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 303d764a1dda29ecf9494430b320665d SHA-1: 58f9adb7217c9be563292a7c99c7882669ee9fa5 SHA-256: 8c540741382f140ffc55458865f8dd5db937b7020e2ecc2cf6027f561b591fc4
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains, indicating a link farm or SEO spamming operation. ClamAV and ML classifiers flagged this as malicious, specifically a phishing trojan. The document body, though heavily obfuscated, suggests a lure related to personal statements or academic content, likely to entice clicks on the embedded malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • 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 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://xajibur.ru/wix?keyword=describe+the+world+you+come+from+personal+statement PDF link annotation
    • http://segwaywheelchair.ru/city_block_translation_in_spanishjy9o1.pdfIn PDF document text
    • http://elinekici.online/womejekisudafamey5qk.pdfIn PDF document text
    • http://instapodarok.site/zomenusimoriwepad8whve.pdfIn PDF document text
    • http://hopecommunitynaz.com/new_gospel_praise_and_worship_songs_2019pbmjp.pdfIn PDF document text
    • http://wowit.pro/computer_basic_course_hindi_notesere9f.pdfIn PDF document text
    • http://streamsweets.com/roworupiwalofanuwduke5.pdfIn PDF document text
    • http://nuwevabufa.mypressonline.com/zalegaxikul.pdfIn PDF document text
    • http://vowujebotoza.mywebcommunity.org/how_do_you_do_ratios_with_fractions.pdfIn PDF document text
    • http://jopkapopka.online/zanitilokuy39ck.pdfIn PDF document text
    • http://garantiya62.ru/android_o_linux_kernel_versiondhz55.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c053410-8c5b-45b5-b84d-15cb31bfe422/tamil_movie_story_script_format.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/034ab984-1f6d-4c57-818e-5f17f4636550/what_happens_in_the_original_snow_white.pdfIn PDF document text
    • https://70848fb0-0fd0-490a-9360-2ffa38fc212c.filesusr.com/ugd/08e331_4d9ab94d6ae44798b351f4b509bea94f.pdf?index=trueIn PDF document text
    • http://xuxerutiwuv.onlinewebshop.net/vejawove.pdfIn PDF document text
    • https://b1fdf235-84a1-4479-ba44-7fc4a4f983d7.filesusr.com/ugd/afcd87_d579476ab3ae4fa6b2a1eb4e6dde5bc6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/329071f5-3f7b-480d-be6b-2c40dc847841/verb_list_acting.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e445fabf-5a8b-4393-a7e0-0af66deb3341/how_do_i_stop_my_bosch_washing_machine_mid_cycle.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c7e8eaa-e57a-4fde-91e0-69eccd71346f/casdon_-_dyson_ball_vacuum_toy_vacuum_with_working_suction_and_sounds_2_lbs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a4fd309b-c5f6-4e6c-b6c5-4c42b1c43877/tabaginu.pdfIn PDF document text
    • https://c2c662fa-00ac-4c69-bf5d-04da7d6c99e2.filesusr.com/ugd/9b33c5_c944d9ad26964300ad74eea6d4657973.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d8705cb-8593-4cb9-b925-0f9af553258b/gewunadu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bfa53e87-2d0b-4b87-a795-762ddcb81370/how_to_get_rid_of_orange_peel_textured_walls.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ba1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BA1 5728 bytes
SHA-256: 8dd6ec0358a7eac769f8f6ed8fcb96c282000e813f1d33c3e59c80f49e2a75e9
font_01_sfnt_off00011f0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F0E 10472 bytes
SHA-256: 639bc230397245b3d052ce41c240ed566f176a939e1bc62c37ee932131499020