Malicious PDF — malware analysis report

Static analysis result for SHA-256 53d411600252f2ef…

MALICIOUS

PDF

81.8 KB Created: 2021-04-15 17:43:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: edbe0132aade62a209fe5429d128ed70 SHA-1: 9f28fa9bd3fbd95249a046b27ef76c9ccf2c7dd0 SHA-256: 53d411600252f2ef2197482cceda9eee4565d41aa3e1e9aa6b255c3ecbc87886
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous URLs point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://nipisod.ru/strik?utm_term=who+moved+my+cheese+study+guide+answers PDF link annotation
    • https://cdn.sqhk.co/nipigagavadu/Fhahghg/jupofoxunilodaxusuzixajej.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455907/normal_5fc6dd96887b5.pdfIn PDF document text
    • https://somubafe.weebly.com/uploads/1/3/4/4/134444697/1fca456b3.pdfIn PDF document text
    • http://luwinilulurop.mywebcommunity.org/58337925522.pdfIn PDF document text
    • https://valofapapedor.weebly.com/uploads/1/3/1/1/131164243/pijobamisat_dedaz_zifavujafa.pdfIn PDF document text
    • http://didazema.mypressonline.com/cardiopatia_hipertensiva_medigraphic.pdfIn PDF document text
    • https://cdn.sqhk.co/feduminaro/Jhhhege/90265294375.pdfIn PDF document text
    • https://nanavefog.weebly.com/uploads/1/3/0/7/130775134/28d53b8e6b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414172/normal_6028f6399731e.pdfIn PDF document text
    • https://cdn.sqhk.co/tukawezezo/kG4Pgip/key_components_of_a_business_plan.pdfIn PDF document text
    • https://retinagarar.weebly.com/uploads/1/3/4/3/134319249/nefedoxojigu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386593/normal_602385ae922d9.pdfIn PDF document text
    • https://zerimesatevig.weebly.com/uploads/1/3/4/8/134879836/wuranojibul.pdfIn PDF document text
    • http://sokobumoxagug.scienceontheweb.net/antibiotics_guidelines.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471092/normal_60026e9c5de3d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443371/normal_602bf565321e5.pdfIn PDF document text
    • https://cdn.sqhk.co/tefozakozup/9ifhgjf/slingshot_shoot_arrows.pdfIn PDF document text
    • https://cdn.sqhk.co/dulunukosep/gjHnVhh/solitary_lung_nodule_bts_guidelines.pdfIn PDF document text
    • https://cdn.sqhk.co/laxegipo/aEz6zkd/luke_bryan_songs_youtube.pdfIn PDF document text
    • https://cdn.sqhk.co/xederebat/gejfZsY/air_control_systems_jacksonville_fl.pdfIn PDF document text
    • https://cdn.sqhk.co/ropobemuma/eieijbG/large_running_dog_breeds_uk.pdfIn PDF document text
    • https://veralekixa.weebly.com/uploads/1/3/1/0/131069874/485eeef063.pdfIn PDF document text
    • https://cdn.sqhk.co/guwaloxipete/jaSZehi/best_armor_in_rlcraft_minecraft.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://tikeresepujel.onlinewebshop.net/wuzesubaxana.pdfIn PDF document text
    • http://todifisafi.atwebpages.com/88879151057.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f4ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4CA 5472 bytes
SHA-256: 21cafbd9943b7479289a6c051a38754db2e738725a96f593d466d712c6034094
font_01_sfnt_off0001075d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1075D 10540 bytes
SHA-256: 2aeaa180753be2fef1aeafd482a969588c10b9f2123d14a3fc475c8bb1949db2
font_02_sfnt_off00012b51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B51 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e