Malicious PDF — malware analysis report

Static analysis result for SHA-256 872dba6fb700da31…

MALICIOUS

PDF

102.4 KB Created: 2021-04-09 11:21:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d35efc2222d900f5e45b54ddae1d55da SHA-1: 9e9ad5434d863dbd9290204e2713e4df8d389af2 SHA-256: 872dba6fb700da31299513ac3038498f8fed78b459ab8d065a6fcae33fcc4b73
186 Risk Score

Malware Insights

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

The PDF contains a significant number of external links, many pointing to disposable domains, indicating a link farm for SEO or malicious redirection. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is designed to drive traffic to potentially harmful external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/strik?utm_term=what+is+death+note+volume+13
    • https://wojazaxu.weebly.com/uploads/1/3/4/5/134589930/xuziro.pdf
    • http://zevewidojodot.mywebcommunity.org/advantages_of_jumping_rope_exercise.pdf
    • http://tufuwavaziga.mygamesonline.org/pre-wired_aswc-1_harness.pdf
    • https://gikesusemu.weebly.com/uploads/1/3/4/7/134775173/78ece81831de.pdf
    • http://birebap.scienceontheweb.net/soruwobujopuboviridexujiw.pdf
    • http://bibopasaxuvibu.mypressonline.com/how_to_read_sewing_needle_sizes.pdf
    • https://sudarotabodubig.weebly.com/uploads/1/3/1/4/131407445/fadezexamop_latotixi.pdf
    • https://wefigofotagovir.weebly.com/uploads/1/3/4/8/134864379/mewulo_kudakuvoges.pdf
    • http://dupuladusudired.mypressonline.com/biodegradation_of_lignin.pdf
    • https://fiwisito.weebly.com/uploads/1/3/4/7/134715438/tukubujopak.pdf
    • http://rufawefojag.sportsontheweb.net/canal_av_desbalanceado.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/gajakelegeza/47589368206.pdf
    • https://s3.amazonaws.com/fotojipifuzitul/how_do_you_feel_today_answer.pdf
    • http://ferugasa.epizy.com/gevevatuzabafolusik.pdf
    • http://naxefugoxodikow.atwebpages.com/wawakujutunovaxotukiwiv.pdf
    • https://2ed821ec-8078-4e74-b11b-c5cec6a88262.filesusr.com/ugd/65e777_f638abafa2ad408ab88da867270e813d.pdf?index=true
    • http://dinexun.epizy.com/40379897264.pdf
    • http://lepetape.epizy.com/ncert_class_8_science_cell_structure_and_function.pdf
    • http://zasexizo.rf.gd/what_are_basic_linux_commands.pdf
    • https://4a31e3f8-49e3-4331-b1a9-c0bb7a6b9dbc.filesusr.com/ugd/599f1c_0faf98ac6a774704a4085f06ba4cf4cd.pdf?index=true
    • https://s3.amazonaws.com/rakabexozu/intraorbital_foreign_body_reporting_course.pdf
    • https://a1d3e036-d9a1-4be1-9d2f-eedbb581cb22.filesusr.com/ugd/3ce946_d6ad131347a44707a9f7a6774a389948.pdf?index=true
    • https://a6f18165-9bfd-46c9-8f51-0ab50cd0b687.filesusr.com/ugd/265c7a_fc62d9cc0ae14daa9fb07e0dccf6714c.pdf?index=true
    • https://s3.amazonaws.com/davawina/electrical_pid_symbols.pdf
    • http://nivuzujanux.myartsonline.com/22151819192.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/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off0000f9b5.bin
d74c13607ed6db15389c02039b70a8596c294b5af58c6486e51aa827ce3dcc6e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xF9B5 17112 bytes
font_01_sfnt_off00013018.bin
6666688496126952e6a8b3f7d95dae3dcb292f12b62d6149e15b5a9522056e64
pdf-font-stream PDF embedded font (sfnt) at offset 0x13018 5140 bytes
font_02_sfnt_off0001417b.bin
ab01ab46cd3d0fc309fbe384de8a7abc1c635a32433db6c6dc235617c41bb504
pdf-font-stream PDF embedded font (sfnt) at offset 0x1417B 11628 bytes
font_03_sfnt_off0001687b.bin
c26df5a654703d82c4b49e3d99d7624c72720c83e2144c41d2616ef18af3c653
pdf-font-stream PDF embedded font (sfnt) at offset 0x1687B 16076 bytes
font_04_sfnt_off00017d29.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x17D29 4324 bytes