Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4c8fdf190a0b0e8…

MALICIOUS

PDF

80.9 KB Created: 2021-04-01 14:44:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: a4dd9b2752aacd966d44abb873b49027 SHA-1: 6f617b5bb503167d0bf0d329f1a9b9138de27dba SHA-256: a4c8fdf190a0b0e8cc89b6831d06ec133d37efa3f0216fda6906ecf688099088
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF contains numerous external links, many pointing to disposable domains, suggesting a link farm or phishing operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to exploiting PDF vulnerabilities or redirecting users to malicious sites. No scripts were extracted, but the presence of external links and the nature of the heuristics suggest an attempt to deliver a second-stage payload or phish credentials.

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://bologen.ru/award?keyword=abbyy+pdf+transformer+12+%25D1%2581%25D0%25B5%25D1%2580%25D0%25B8%25D0%25B9%25D0%25BD%25D1%258B%25D0%25B9+%25D0%25BD%25D0%25BE%25D0%25BC%25D0%25B5%25D1%2580 PDF link annotation
    • http://titanof-filtr.ru/vokuwinezikanawinavepovub74b8.pdfIn PDF document text
    • https://cdn.sqhk.co/moxinivo/PYZgjgj/26781132264.pdfIn PDF document text
    • https://cdn.sqhk.co/rugugojeba/2TJdvsU/53954236149.pdfIn PDF document text
    • https://cdn.sqhk.co/mekurapiw/jhijjhn/xepiguloxipefimonozasa.pdfIn PDF document text
    • http://autokenn.com/push_the_buttons_song0jx3p.pdfIn PDF document text
    • https://cdn.sqhk.co/tagisaxozof/jfUPhgY/xivutexajivujafa.pdfIn PDF document text
    • https://cdn.sqhk.co/xovikojux/iwejiSb/stickman_jump_shadow_revenge_mod_apk.pdfIn PDF document text
    • https://cdn.sqhk.co/ligumorik/YxpPljf/real_boxing_ko_fighting_game_download.pdfIn PDF document text
    • https://cdn.sqhk.co/pujixefan/eueSeDf/84669997530.pdfIn PDF document text
    • https://cdn.sqhk.co/mugukawi/hcjacRA/picsart_background_hd_images_download_car.pdfIn PDF document text
    • https://cdn.sqhk.co/zupuguvawaj/dhaJhee/xakawebixus.pdfIn PDF document text
    • https://cdn.sqhk.co/kavuluxaja/hbfMgf7/pocket_rocket_2_fuel_consumption.pdfIn PDF document text
    • https://cdn.sqhk.co/lodikorep/axhe0if/65778029889.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/gumegulaxi/jingle_bells_guitar_tab.pdfIn PDF document text
    • https://c7f0abc7-d23b-482d-bd16-0771495bb668.filesusr.com/ugd/bb13a2_46212f7e42ae4596b2520e9690f3380b.pdf?index=trueIn PDF document text
    • https://d7e981a8-8c4a-445e-aef0-60d3d4911bd2.filesusr.com/ugd/65d69c_f62249637f9b4121a8fb2e7788b3aeb4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/fifomi/oracion_de_guerra_espiritual_cristiana_por_los_hijos.pdfIn PDF document text
    • https://s3.amazonaws.com/bulikowexunepov/wuvatiwiruluzowimofijusod.pdfIn PDF document text
    • https://fdb4f28e-c637-431f-967d-457feef73efb.filesusr.com/ugd/cf5aa9_07b6c36a483c4281b8de9bd983f7d1c1.pdf?index=trueIn PDF document text
    • https://58552d80-c20c-4e4f-99b9-91bedbcc07a3.filesusr.com/ugd/c18496_512b39f951144da5859b4176df298d9e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kavugusepe/89471523196.pdfIn PDF document text
    • https://a35aa970-3e4e-4c20-be1f-53d10001bce9.filesusr.com/ugd/af4e73_c17f823eab65429c8f3a33945b28b537.pdf?index=trueIn 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_off0000ec96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC96 6496 bytes
SHA-256: f2cf4ee2f93ed176dd73c7a221db5453c6a923741e42ccc260e57236e8dbbcf5
font_01_sfnt_off00010192.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10192 15964 bytes
SHA-256: 6df647d17805aaafff2229c458d5fcd47f01cbc6ba481a97c0dd3f2b696effc8